Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

21 files changed, 2998 insertions, 0 deletions

diff --git a/comm/mailnews/mapi/mapihook/build/MapiProxy.def b/comm/mailnews/mapi/mapihook/build/MapiProxy.def
new file mode 100644
index 0000000000..4da08eb7d3
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/build/MapiProxy.def
@@ -0,0 +1,13 @@
+; This Source Code Form is subject to the terms of the Mozilla Public
+; License, v. 2.0. If a copy of the MPL was not distributed with this
+; file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+LIBRARY         MapiProxy.dll
+
+EXPORTS
+                DllGetClassObject    PRIVATE
+                DllCanUnloadNow      PRIVATE
+                GetProxyDllInfo      PRIVATE
+                DllRegisterServer    PRIVATE
+                DllUnregisterServer  PRIVATE
+
diff --git a/comm/mailnews/mapi/mapihook/build/module.ver b/comm/mailnews/mapi/mapihook/build/module.ver
new file mode 100644
index 0000000000..7691020c26
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/build/module.ver
@@ -0,0 +1,6 @@
+WIN32_MODULE_FILEVERSION=0,8,0,0
+WIN32_MODULE_FILEVERSION_STRING=0.8
+WIN32_MODULE_COPYRIGHT=ŠThunderbird and Mozilla Developers, according to the MPL 1.1/GPL 2.0/LGPL 2.1 licenses, as applicable.
+WIN32_MODULE_COMPANYNAME=Mozilla.org
+WIN32_MODULE_TRADEMARKS=Mozilla
+WIN32_MODULE_COMMENT=Mozilla Thunderbird Thunderbird MAPI Proxy Dll
diff --git a/comm/mailnews/mapi/mapihook/build/moz.build b/comm/mailnews/mapi/mapihook/build/moz.build
new file mode 100644
index 0000000000..9832a5cb05
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/build/moz.build
@@ -0,0 +1,56 @@
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+SharedLibrary("MapiProxy")
+
+OS_LIBS += [
+    "rpcrt4",
+]
+
+LOCAL_INCLUDES += ["/comm/mailnews/mapi/include"]
+
+SOURCES += ["!dlldata.c", "!msgMapi_i.c", "!msgMapi_p.c"]
+
+GeneratedFile(
+    "dlldata.c",
+    "msgMapi.h",
+    "msgMapi_i.c",
+    "msgMapi_p.c",
+    inputs=["msgMapi.idl"],
+    script="/build/midl.py",
+    entry_point="midl",
+    flags=[
+        "-I",
+        SRCDIR,
+        "-I",
+        TOPSRCDIR + "/comm/mailnews/mapi/include",
+    ],
+)
+
+EXPORTS += [
+    "!msgMapi.h",
+    "!msgMapi_i.c",
+]
+
+for var in ("REGISTER_PROXY_DLL", "UNICODE", "_UNICODE"):
+    DEFINES[var] = True
+
+DEFFILE = "MapiProxy.def"
+
+# The Windows MIDL code generator creates things like:
+#
+#   #endif !_MIDL_USE_GUIDDEF_
+#
+# which clang-cl complains about.  MSVC doesn't, so turn this warning off.
+if CONFIG["CC_TYPE"] == "clang-cl":
+    CFLAGS += ["-Wno-extra-tokens"]
+
+# clang-cl complains about these in generated code:
+if CONFIG["CC_TYPE"] == "clang-cl":
+    CFLAGS += [
+        "-Wno-extern-initializer",
+        "-Wno-missing-braces",
+        "-Wno-unused-const-variable",
+    ]
diff --git a/comm/mailnews/mapi/mapihook/build/msgMapi.idl b/comm/mailnews/mapi/mapihook/build/msgMapi.idl
new file mode 100644
index 0000000000..e2738ae8e1
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/build/msgMapi.idl
@@ -0,0 +1,125 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This idl will be compiled by MIDL.  MS-COM is used
+// as bridge between MAPI clients and the Mozilla.
+
+import "unknwn.idl";
+
+typedef struct
+{
+    unsigned long   ulReserved;
+    unsigned long   flFlags;           /* Flags */
+    unsigned long   nPosition_NotUsed; /* character in text to be replaced by attachment */
+    LPSTR           lpszPathName;      /* Full path name including file name */
+    LPSTR           lpszFileName;      /* Real (original) file name */
+    unsigned char * lpFileType_NotUsed ;
+} nsMapiFileDesc, * lpnsMapiFileDesc;
+
+
+typedef struct
+{
+    unsigned long    ulReserved;
+    unsigned long    ulRecipClass; /* MAPI_TO, MAPI_CC, MAPI_BCC, MAPI_ORIG    */
+    LPSTR            lpszName;     /* Recipient name to display */
+    LPSTR            lpszAddress;  /* Recipient email address */
+    unsigned long    ulEIDSize_NotUsed;
+    unsigned char  * lpEntryID_NotUsed ;
+} nsMapiRecipDesc, * lpnsMapiRecipDesc;
+
+typedef struct
+{
+    unsigned long ulReserved;
+    LPSTR             lpszSubject;                      /* Message Subject */
+    LPSTR             lpszNoteText;                     /* Message Text */
+    LPSTR             lpszMessageType;
+    LPSTR             lpszDateReceived;                 /* in YYYY/MM/DD HH:MM format */
+    LPSTR             lpszConversationID_NotUsed;       /* conversation thread ID */
+    unsigned long     flFlags;                          /* unread,return receipt */
+    lpnsMapiRecipDesc lpOriginator;                     /* Originator descriptor  */
+    unsigned long     nRecipCount;                      /* Number of recipients   */
+    [size_is (nRecipCount)] lpnsMapiRecipDesc lpRecips; /* Recipient descriptors  */
+    unsigned long     nFileCount;                       /* # of file attachments  */
+    [size_is (nFileCount)] lpnsMapiFileDesc lpFiles;    /* Attachment descriptors */
+} nsMapiMessage, * lpnsMapiMessage;
+
+typedef struct
+{
+    unsigned long     ulReserved;
+    unsigned long     flFlags;               /* Flags */
+    unsigned long     nPosition_NotUsed;     /* character in text to be replaced by attachment */
+    LPWSTR            lpszPathName;          /* Full path name including file name */
+    LPWSTR            lpszFileName;          /* Real (original) file name */
+    unsigned char*    lpFileType_NotUsed;
+} nsMapiFileDescW, *lpnsMapiFileDescW;
+
+typedef struct
+{
+    unsigned long      ulReserved;
+    unsigned long      ulRecipClass;  /* MAPI_TO, MAPI_CC, MAPI_BCC, MAPI_ORIG    */
+    LPWSTR             lpszName;      /* Recipient name to display */
+    LPWSTR             lpszAddress;   /* Recipient email address */
+    unsigned long      ulEIDSize_NotUsed;
+    unsigned char*     lpEntryID_NotUsed;
+} nsMapiRecipDescW, *lpnsMapiRecipDescW;
+
+typedef struct
+{
+    unsigned long           ulReserved;
+    LPWSTR                  lpszSubject;                 /* Message Subject */
+    LPWSTR                  lpszNoteText;                /* Message Text */
+    LPWSTR                  lpszMessageType;
+    LPWSTR                  lpszDateReceived;            /* in YYYY/MM/DD HH:MM format */
+    LPWSTR                  lpszConversationID_NotUsed;  /* conversation thread ID */
+    unsigned long           flFlags;                     /* unread,return receipt */
+    lpnsMapiRecipDescW      lpOriginator;                /* Originator descriptor  */
+    unsigned long           nRecipCount;                 /* Number of recipients   */
+    [size_is (nRecipCount)] lpnsMapiRecipDescW lpRecips; /* Recipient descriptors  */
+    unsigned long           nFileCount;                  /* # of file attachments  */
+    [size_is (nFileCount)]  lpnsMapiFileDescW lpFiles;   /* Attachment descriptors */
+} nsMapiMessageW, *lpnsMapiMessageW;
+
+[
+    object,
+    uuid(6EDCD38E-8861-11d5-A3DD-00B0D0F3BAA7),
+    helpstring("nsIMapi Interface"),
+    pointer_default(unique)
+]
+
+interface nsIMapi : IUnknown
+{
+    HRESULT Login([in] unsigned long aUIArg, [in, unique, max_is(256)] LPSTR aLogin,
+                  [in, unique, max_is(256)] LPSTR aPassWord, [in] unsigned long aFlags,
+                  [out] unsigned long *aSessionId);
+
+    HRESULT Initialize();
+    HRESULT IsValid();
+    HRESULT IsValidSession([in] unsigned long aSession);
+
+    HRESULT SendMail([in] unsigned long aSession, [in, unique] lpnsMapiMessage aMessage,
+                     [in] unsigned long aFlags, [in] unsigned long aReserved) ;
+
+    HRESULT SendDocuments([in] unsigned long aSession,
+                          [in, unique] LPSTR aDelimChar, [in, unique] LPSTR aFilePaths,
+                          [in, unique] LPSTR aFileNames, [in] ULONG aFlags);
+
+    HRESULT FindNext([in] unsigned long aSession, [in] ULONG ulUIParam, [in, unique] const LPSTR lpszMessageType,
+                     [in, unique] const LPSTR lpszSeedMessageID, [in] ULONG flFlags, [in] ULONG ulReserved,
+                     [in] [out] char lpszMessageID[64] ) ;
+
+    HRESULT ReadMail([in] unsigned long lhSession, [in] ULONG ulUIParam, [in, unique] LPSTR lpszMessageID,
+                     [in] ULONG flFlags, [in] ULONG ulReserved, [out] lpnsMapiMessage *lppMessage);
+
+    HRESULT DeleteMail([in] unsigned long lhSession, [in] ULONG ulUIParam, [in, unique] LPSTR lpszMessageID,
+                       [in] ULONG flFlags, [in] ULONG ulReserved);
+
+    HRESULT SaveMail([in] unsigned long lhSession, [in] ULONG ulUIParam, [in, unique] lpnsMapiMessage lppMessage,
+                     [in] ULONG flFlags, [in] ULONG ulReserved, [in, unique] LPSTR lpszMessageID);
+
+    HRESULT SendMailW([in] unsigned long aSession, [in, unique] lpnsMapiMessageW aMessage,
+                      [in] unsigned long aFlags, [in] unsigned long aReserved);
+
+    HRESULT Logoff(unsigned long aSession);
+    HRESULT CleanUp();
+};
diff --git a/comm/mailnews/mapi/mapihook/moz.build b/comm/mailnews/mapi/mapihook/moz.build
new file mode 100644
index 0000000000..2160ce3345
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/moz.build
@@ -0,0 +1,10 @@
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+DIRS += [
+    "public",
+    "build",
+    "src",
+]
diff --git a/comm/mailnews/mapi/mapihook/public/moz.build b/comm/mailnews/mapi/mapihook/public/moz.build
new file mode 100644
index 0000000000..12f8019242
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/public/moz.build
@@ -0,0 +1,10 @@
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+XPIDL_SOURCES += [
+    "nsIMapiSupport.idl",
+]
+
+XPIDL_MODULE = "mapihook"
diff --git a/comm/mailnews/mapi/mapihook/public/nsIMapiSupport.idl b/comm/mailnews/mapi/mapihook/public/nsIMapiSupport.idl
new file mode 100644
index 0000000000..39a947ae7a
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/public/nsIMapiSupport.idl
@@ -0,0 +1,42 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+/**
+ * This interface provides support for registering Mozilla as a COM component
+ * for extending the use of Mail/News through Simple MAPI.
+ *
+ */
+
+[uuid(2907B676-C4BD-49af-880A-E27A0616291E)]
+interface nsIMapiSupport : nsISupports {
+
+   /** Initiates MAPI support
+    */
+
+   void initializeMAPISupport();
+
+   /**  Shuts down the MAPI support
+    */
+
+   void shutdownMAPISupport();
+
+   /**  registerServer - register the mapi DLL with the desktop
+    *   Typically called by the window shell service when we are
+    *   made the default mail app
+    */
+   void registerServer();
+
+   /**  unRegisterServer - unregister the mapi DLL with the desktop
+    *   Typically called by the window shell service when we are
+    *   removed as the default mail app.
+    */
+   void unRegisterServer();
+};
+
+%{C++
+#define NS_IMAPISUPPORT_CONTRACTID    "@mozilla.org/mapisupport;1"
+#define NS_IMAPISUPPORT_CLASSNAME     "Mozilla MAPI Support"
+%}
diff --git a/comm/mailnews/mapi/mapihook/src/Registry.cpp b/comm/mailnews/mapi/mapihook/src/Registry.cpp
new file mode 100644
index 0000000000..bf57e31e57
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/Registry.cpp
@@ -0,0 +1,249 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#undef _UNICODE
+#undef UNICODE
+
+#include <objbase.h>
+#include "nsString.h"
+#include "Registry.h"
+
+#define MAPI_PROXY_DLL_NAME u"MapiProxy.dll"
+#define MAPI_STARTUP_ARG L" /MAPIStartUp"
+#define MAX_SIZE 2048
+
+// Size of a CLSID as a string
+const int CLSID_STRING_SIZE = 39;
+
+// Proxy/Stub Dll Routines
+
+typedef HRESULT(__stdcall ProxyServer)();
+
+// Convert a CLSID to a WCHAR string.
+
+BOOL CLSIDtoWchar(const CLSID& clsid, WCHAR* szCLSID) {
+  // Get CLSID
+  HRESULT hr = StringFromCLSID(clsid, &szCLSID);
+  if (FAILED(hr)) return FALSE;
+  return TRUE;
+}
+
+// Create a key and set its value.
+
+BOOL setKeyAndValue(nsAutoString keyName, const WCHAR* subKey,
+                    const WCHAR* theValue) {
+  HKEY hKey;
+  BOOL retValue = TRUE;
+
+  nsAutoString theKey(keyName);
+  if (subKey != NULL) {
+    theKey += L"\\";
+    theKey += subKey;
+  }
+
+  // Create and open key and subkey.
+  long lResult = RegCreateKeyExW(HKEY_CLASSES_ROOT, theKey.get(), 0, NULL,
+                                 REG_OPTION_NON_VOLATILE, KEY_ALL_ACCESS, NULL,
+                                 &hKey, NULL);
+  if (lResult != ERROR_SUCCESS) return FALSE;
+
+  // Set the Value.
+  if (theValue != NULL) {
+    lResult = RegSetValueExW(hKey, NULL, 0, REG_SZ, (BYTE*)theValue,
+                             wcslen(theValue) + 1);
+    if (lResult != ERROR_SUCCESS) retValue = FALSE;
+  }
+
+  RegCloseKey(hKey);
+  return retValue;
+}
+
+// Delete a key and all of its descendents.
+
+LONG recursiveDeleteKey(HKEY hKeyParent,            // Parent of key to delete
+                        const WCHAR* lpszKeyChild)  // Key to delete
+{
+  // Open the child.
+  HKEY hKeyChild;
+  LONG lRes =
+      RegOpenKeyExW(hKeyParent, lpszKeyChild, 0, KEY_ALL_ACCESS, &hKeyChild);
+  if (lRes != ERROR_SUCCESS) {
+    return lRes;
+  }
+
+  // Enumerate all of the descendants of this child.
+  FILETIME time;
+  WCHAR szBuffer[MAX_SIZE];
+  DWORD dwSize = MAX_SIZE;
+  while (RegEnumKeyExW(hKeyChild, 0, szBuffer, &dwSize, NULL, NULL, NULL,
+                       &time) == S_OK) {
+    // Delete the descendants of this child.
+    lRes = recursiveDeleteKey(hKeyChild, szBuffer);
+    if (lRes != ERROR_SUCCESS) {
+      // Cleanup before exiting.
+      RegCloseKey(hKeyChild);
+      return lRes;
+    }
+    dwSize = MAX_SIZE;
+  }
+
+  // Close the child.
+  RegCloseKey(hKeyChild);
+
+  // Delete this child.
+  return RegDeleteKeyW(hKeyParent, lpszKeyChild);
+}
+
+void RegisterProxy() {
+  HINSTANCE h = NULL;
+  ProxyServer* RegisterFunc = NULL;
+
+  WCHAR szModule[MAX_SIZE];
+  WCHAR* pTemp = NULL;
+
+  HMODULE hModule = GetModuleHandleW(NULL);
+  DWORD dwResult =
+      ::GetModuleFileNameW(hModule, szModule, sizeof(szModule) / sizeof(WCHAR));
+  if (dwResult == 0) return;
+
+  pTemp = wcsrchr(szModule, L'\\');
+  if (pTemp == NULL) return;
+
+  *pTemp = '\0';
+  nsAutoString proxyPath(szModule);
+
+  proxyPath += u"\\";
+  proxyPath += MAPI_PROXY_DLL_NAME;
+
+  h = LoadLibraryW(proxyPath.get());
+  if (h == NULL) return;
+
+  RegisterFunc = (ProxyServer*)GetProcAddress(h, "DllRegisterServer");
+  if (RegisterFunc) RegisterFunc();
+
+  FreeLibrary(h);
+}
+
+void UnRegisterProxy() {
+  HINSTANCE h = NULL;
+  ProxyServer* UnRegisterFunc = NULL;
+
+  WCHAR szModule[MAX_SIZE];
+  WCHAR* pTemp = NULL;
+
+  HMODULE hModule = GetModuleHandleW(NULL);
+  DWORD dwResult =
+      ::GetModuleFileNameW(hModule, szModule, sizeof(szModule) / sizeof(WCHAR));
+  if (dwResult == 0) return;
+
+  pTemp = wcsrchr(szModule, L'\\');
+  if (pTemp == NULL) return;
+
+  *pTemp = '\0';
+  nsAutoString proxyPath(szModule);
+
+  proxyPath += u"\\";
+  proxyPath += MAPI_PROXY_DLL_NAME;
+
+  h = LoadLibraryW(proxyPath.get());
+  if (h == NULL) return;
+
+  UnRegisterFunc = (ProxyServer*)GetProcAddress(h, "DllUnregisterServer");
+  if (UnRegisterFunc) UnRegisterFunc();
+
+  FreeLibrary(h);
+}
+
+// Register the component in the registry.
+
+HRESULT RegisterServer(const CLSID& clsid,           // Class ID
+                       const WCHAR* szFriendlyName,  // Friendly Name
+                       const WCHAR* szVerIndProgID,  // Programmatic
+                       const WCHAR* szProgID)        //   IDs
+{
+  HMODULE hModule = GetModuleHandleW(NULL);
+  WCHAR szModuleName[MAX_SIZE];
+  WCHAR szCLSID[CLSID_STRING_SIZE];
+
+  nsAutoString independentProgId(szVerIndProgID);
+  nsAutoString progId(szProgID);
+
+  DWORD dwResult = ::GetModuleFileNameW(hModule, szModuleName,
+                                        sizeof(szModuleName) / sizeof(WCHAR));
+
+  if (dwResult == 0) return S_FALSE;
+
+  nsAutoString moduleName(szModuleName);
+  nsAutoString registryKey(L"CLSID\\");
+
+  moduleName += MAPI_STARTUP_ARG;
+
+  // Convert the CLSID into a WCHAR.
+  if (!CLSIDtoWchar(clsid, szCLSID)) return S_FALSE;
+  registryKey += szCLSID;
+
+  // Add the CLSID to the registry.
+  if (!setKeyAndValue(registryKey, NULL, szFriendlyName)) return S_FALSE;
+
+  if (!setKeyAndValue(registryKey, L"LocalServer32", moduleName.get()))
+    return S_FALSE;
+
+  // Add the ProgID subkey under the CLSID key.
+  if (!setKeyAndValue(registryKey, L"ProgID", szProgID)) return S_FALSE;
+
+  // Add the version-independent ProgID subkey under CLSID key.
+  if (!setKeyAndValue(registryKey, L"VersionIndependentProgID", szVerIndProgID))
+    return S_FALSE;
+
+  // Add the version-independent ProgID subkey under HKEY_CLASSES_ROOT.
+  if (!setKeyAndValue(independentProgId, NULL, szFriendlyName)) return S_FALSE;
+  if (!setKeyAndValue(independentProgId, L"CLSID", szCLSID)) return S_FALSE;
+  if (!setKeyAndValue(independentProgId, L"CurVer", szProgID)) return S_FALSE;
+
+  // Add the versioned ProgID subkey under HKEY_CLASSES_ROOT.
+  if (!setKeyAndValue(progId, NULL, szFriendlyName)) return S_FALSE;
+  if (!setKeyAndValue(progId, L"CLSID", szCLSID)) return S_FALSE;
+
+  RegisterProxy();
+
+  return S_OK;
+}
+
+LONG UnregisterServer(const CLSID& clsid,           // Class ID
+                      const WCHAR* szVerIndProgID,  // Programmatic
+                      const WCHAR* szProgID)        //   IDs
+{
+  LONG lResult = S_OK;
+
+  // Convert the CLSID into a char.
+
+  WCHAR szCLSID[CLSID_STRING_SIZE];
+  if (!CLSIDtoWchar(clsid, szCLSID)) return S_FALSE;
+
+  UnRegisterProxy();
+
+  nsAutoString registryKey(L"CLSID\\");
+  registryKey += szCLSID;
+
+  lResult = recursiveDeleteKey(HKEY_CLASSES_ROOT, registryKey.get());
+  if (lResult == ERROR_SUCCESS || lResult == ERROR_FILE_NOT_FOUND)
+    return lResult;
+
+  registryKey += L"\\LocalServer32";
+
+  // Delete only the path for this server.
+
+  lResult = recursiveDeleteKey(HKEY_CLASSES_ROOT, registryKey.get());
+  if (lResult != ERROR_SUCCESS && lResult != ERROR_FILE_NOT_FOUND)
+    return lResult;
+
+  // Delete the version-independent ProgID Key.
+  lResult = recursiveDeleteKey(HKEY_CLASSES_ROOT, szVerIndProgID);
+  if (lResult != ERROR_SUCCESS && lResult != ERROR_FILE_NOT_FOUND)
+    return lResult;
+
+  lResult = recursiveDeleteKey(HKEY_CLASSES_ROOT, szProgID);
+
+  return lResult;
+}
diff --git a/comm/mailnews/mapi/mapihook/src/Registry.h b/comm/mailnews/mapi/mapihook/src/Registry.h
new file mode 100644
index 0000000000..7207694e55
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/Registry.h
@@ -0,0 +1,20 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef _REGISTRY_H_
+#define _REGISTRY_H_
+
+#include <objbase.h>
+
+// This function will register a component in the Registry.
+
+HRESULT RegisterServer(const CLSID& clsid, const WCHAR* szFriendlyName,
+                       const WCHAR* szVerIndProgID, const WCHAR* szProgID);
+
+// This function will unregister a component.
+
+HRESULT UnregisterServer(const CLSID& clsid, const WCHAR* szVerIndProgID,
+                         const WCHAR* szProgID);
+
+#endif
diff --git a/comm/mailnews/mapi/mapihook/src/components.conf b/comm/mailnews/mapi/mapihook/src/components.conf
new file mode 100644
index 0000000000..d69a1df0d5
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/components.conf
@@ -0,0 +1,18 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, you can obtain one at http://mozilla.org/MPL/2.0/.
+
+Classes = [
+    {
+        "cid": "{8967fed2-c8bb-11d5-a3e9-00b0d0f3baa7}",
+        "contract_ids": ["@mozilla.org/mapisupport;1"],
+        "type": "nsMapiSupport",
+        "headers": ["/comm/mailnews/mapi/mapihook/src/msgMapiSupport.h"],
+    }
+]
+
+Categories = {
+    "app-startup": {
+        "Mapi Support": "@mozilla.org/mapisupport;1",
+    }
+}
diff --git a/comm/mailnews/mapi/mapihook/src/moz.build b/comm/mailnews/mapi/mapihook/src/moz.build
new file mode 100644
index 0000000000..f2ef529008
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/moz.build
@@ -0,0 +1,33 @@
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+SOURCES += [
+    "!../build/msgMapi_i.c",
+    "msgMapiFactory.cpp",
+    "msgMapiHook.cpp",
+    "msgMapiImp.cpp",
+    "msgMapiMain.cpp",
+    "msgMapiSupport.cpp",
+    "Registry.cpp",
+]
+
+LOCAL_INCLUDES += ["/comm/mailnews/mapi/include"]
+
+FINAL_LIBRARY = "xul"
+
+OS_LIBS += [
+    "ole32",
+]
+
+DEFINES["UNICODE"] = True
+DEFINES["_UNICODE"] = True
+
+# clang-cl rightly complains about switch on nsresult.
+if CONFIG["CC_TYPE"] == "clang-cl":
+    CXXFLAGS += ["-Wno-switch"]
+
+XPCOM_MANIFESTS += [
+    "components.conf",
+]
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiFactory.cpp b/comm/mailnews/mapi/mapihook/src/msgMapiFactory.cpp
new file mode 100644
index 0000000000..cb99fc04fd
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiFactory.cpp
@@ -0,0 +1,64 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#undef UNICODE
+#undef _UNICODE
+
+#include "msgMapiFactory.h"
+#include "msgMapiImp.h"
+#include "msgMapi.h"
+
+CMapiFactory ::CMapiFactory() : m_cRef(1) {}
+
+CMapiFactory::~CMapiFactory() {}
+
+STDMETHODIMP CMapiFactory::QueryInterface(const IID& aIid, void** aPpv) {
+  if ((aIid == IID_IUnknown) || (aIid == IID_IClassFactory)) {
+    *aPpv = static_cast<IClassFactory*>(this);
+  } else {
+    *aPpv = nullptr;
+    return E_NOINTERFACE;
+  }
+  reinterpret_cast<IUnknown*>(*aPpv)->AddRef();
+  return S_OK;
+}
+
+STDMETHODIMP_(ULONG) CMapiFactory::AddRef() { return ++m_cRef; }
+
+STDMETHODIMP_(ULONG) CMapiFactory::Release() {
+  int32_t temp = --m_cRef;
+  if (m_cRef == 0) {
+    delete this;
+    return 0;
+  }
+
+  return temp;
+}
+
+STDMETHODIMP CMapiFactory::CreateInstance(IUnknown* aUnknownOuter,
+                                          const IID& aIid, void** aPpv) {
+  // Cannot aggregate.
+
+  if (aUnknownOuter != nullptr) {
+    return CLASS_E_NOAGGREGATION;
+  }
+
+  // Create component.
+
+  CMapiImp* pImp = new CMapiImp();
+  if (pImp == nullptr) {
+    return E_OUTOFMEMORY;
+  }
+
+  // Get the requested interface.
+  HRESULT hr = pImp->QueryInterface(aIid, aPpv);
+
+  // Release the IUnknown pointer.
+  // (If QueryInterface failed, component will delete itself.)
+
+  pImp->Release();
+  return hr;
+}
+
+STDMETHODIMP CMapiFactory::LockServer(BOOL aLock) { return S_OK; }
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiFactory.h b/comm/mailnews/mapi/mapihook/src/msgMapiFactory.h
new file mode 100644
index 0000000000..3970b3fa99
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiFactory.h
@@ -0,0 +1,35 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MSG_MAPI_FACTORY_H
+#define MSG_MAPI_FACTORY_H
+
+#include <windows.h>
+#include <objbase.h>
+#include "nspr.h"
+#include "nsISupportsImpl.h"  // ThreadSafeAutoRefCnt
+#include <stdint.h>
+
+class CMapiFactory : public IClassFactory {
+ public:
+  // IUnknown
+
+  STDMETHODIMP QueryInterface(REFIID aIid, void** aPpv);
+  STDMETHODIMP_(ULONG) AddRef(void);
+  STDMETHODIMP_(ULONG) Release(void);
+
+  // IClassFactory
+
+  STDMETHODIMP CreateInstance(LPUNKNOWN aUnkOuter, REFIID aIid, void** aPpv);
+  STDMETHODIMP LockServer(BOOL aLock);
+
+  CMapiFactory();
+
+ private:
+  mozilla::ThreadSafeAutoRefCnt m_cRef;
+
+  virtual ~CMapiFactory();
+};
+
+#endif  // MSG_MAPI_FACTORY_H
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiHook.cpp b/comm/mailnews/mapi/mapihook/src/msgMapiHook.cpp
new file mode 100644
index 0000000000..eb8c9b9fe8
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiHook.cpp
@@ -0,0 +1,934 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#define MAPI_STARTUP_ARG "/MAPIStartUp"
+
+#include <mapidefs.h>
+#include <mapi.h>
+#include <direct.h>
+#include "nsCOMPtr.h"
+#include "nsISupports.h"
+#include "nsIPromptService.h"
+#include "nsIAppShellService.h"
+#include "mozIDOMWindow.h"
+#include "nsIMsgAccountManager.h"
+#include "nsIStringBundle.h"
+#include "nsIPrefService.h"
+#include "nsIPrefBranch.h"
+#include "nsString.h"
+#include "nsUnicharUtils.h"
+#include "nsNativeCharsetUtils.h"
+#include "nsIMsgAttachment.h"
+#include "nsIMsgCompFields.h"
+#include "nsIMsgComposeParams.h"
+#include "nsIMsgCompose.h"
+#include "nsIMsgSend.h"
+#include "nsIMsgComposeService.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsDirectoryServiceUtils.h"
+#include "msgMapi.h"
+#include "msgMapiHook.h"
+#include "msgMapiSupport.h"
+#include "msgMapiMain.h"
+#include "nsThreadUtils.h"
+#include "nsMsgUtils.h"
+#include "nsNetUtil.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/ReentrantMonitor.h"
+#include "mozilla/Components.h"
+#include "nsEmbedCID.h"
+#include "mozilla/Logging.h"
+#include "mozilla/SpinEventLoopUntil.h"
+
+using namespace mozilla::dom;
+
+extern mozilla::LazyLogModule MAPI;  // defined in msgMapiImp.cpp
+
+class MAPISendListener : public nsIMsgSendListener,
+                         public mozilla::ReentrantMonitor {
+ public:
+  MAPISendListener()
+      : ReentrantMonitor("MAPISendListener monitor"), m_done(false) {}
+
+  // nsISupports interface
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+  /* void OnStartSending (in string aMsgID, in uint32_t aMsgSize); */
+  NS_IMETHOD OnStartSending(const char* aMsgID, uint32_t aMsgSize) {
+    return NS_OK;
+  }
+
+  /* void OnProgress (in string aMsgID, in uint32_t aProgress, in uint32_t
+   * aProgressMax); */
+  NS_IMETHOD OnProgress(const char* aMsgID, uint32_t aProgress,
+                        uint32_t aProgressMax) {
+    return NS_OK;
+  }
+
+  /* void OnStatus (in string aMsgID, in wstring aMsg); */
+  NS_IMETHOD OnStatus(const char* aMsgID, const char16_t* aMsg) {
+    return NS_OK;
+  }
+
+  /* void OnStopSending (in string aMsgID, in nsresult aStatus, in wstring aMsg,
+   * in nsIFile returnFile); */
+  NS_IMETHOD OnStopSending(const char* aMsgID, nsresult aStatus,
+                           const char16_t* aMsg, nsIFile* returnFile) {
+    mozilla::ReentrantMonitorAutoEnter mon(*this);
+    m_done = true;
+    NotifyAll();
+    return NS_OK;
+  }
+
+  /* void OnTransportSecurityError( in string msgID, in nsresult status, in
+   * nsITransportSecurityInfo secInfo, in ACString location); */
+  NS_IMETHOD OnTransportSecurityError(const char* msgID, nsresult status,
+                                      nsITransportSecurityInfo* secInfo,
+                                      nsACString const& location) {
+    return NS_OK;
+  }
+
+  /* void OnSendNotPerformed */
+  NS_IMETHOD OnSendNotPerformed(const char* aMsgID, nsresult aStatus) {
+    return OnStopSending(aMsgID, aStatus, nullptr, nullptr);
+  }
+
+  /* void OnGetDraftFolderURI (); */
+  NS_IMETHOD OnGetDraftFolderURI(const char* aMsgID,
+                                 const nsACString& aFolderURI) {
+    return NS_OK;
+  }
+
+  bool IsDone() { return m_done; }
+
+ private:
+  bool m_done;
+  virtual ~MAPISendListener() {}
+};
+
+/// Helper for setting up the hidden window for blind MAPI.
+class MOZ_STACK_CLASS AutoHiddenWindow {
+ public:
+  explicit AutoHiddenWindow(nsresult& rv)
+      : mAppService(do_GetService("@mozilla.org/appshell/appShellService;1")) {
+    mCreatedHiddenWindow = false;
+    rv = mAppService->GetHiddenDOMWindow(getter_AddRefs(mHiddenWindow));
+    if (rv == NS_ERROR_FAILURE) {
+      // Try to get a hidden window. If it doesn't exist, create a hidden
+      // window for us to use.
+      rv = mAppService->CreateHiddenWindow();
+      NS_ENSURE_SUCCESS_VOID(rv);
+      mCreatedHiddenWindow = true;
+      rv = mAppService->GetHiddenDOMWindow(getter_AddRefs(mHiddenWindow));
+    }
+    NS_ENSURE_SUCCESS_VOID(rv);
+  }
+  ~AutoHiddenWindow() {
+    if (mCreatedHiddenWindow) mAppService->DestroyHiddenWindow();
+  }
+  mozIDOMWindowProxy* operator->() { return mHiddenWindow; }
+  operator mozIDOMWindowProxy*() { return mHiddenWindow; }
+
+ private:
+  nsCOMPtr<nsIAppShellService> mAppService;
+  nsCOMPtr<mozIDOMWindowProxy> mHiddenWindow;
+  bool mCreatedHiddenWindow;
+};
+
+NS_IMPL_ISUPPORTS(MAPISendListener, nsIMsgSendListener)
+
+bool nsMapiHook::isMapiService = false;
+
+void nsMapiHook::CleanUp() {
+  // This routine will be fully implemented in future
+  // to cleanup mapi related stuff inside mozilla code.
+}
+
+bool nsMapiHook::DisplayLoginDialog(bool aLogin, char16_t** aUsername,
+                                    char16_t** aPassword) {
+  nsresult rv;
+  bool btnResult = false;
+
+  nsCOMPtr<nsIPromptService> dlgService(
+      do_GetService(NS_PROMPTSERVICE_CONTRACTID, &rv));
+  if (NS_SUCCEEDED(rv) && dlgService) {
+    nsCOMPtr<nsIStringBundleService> bundleService =
+        mozilla::components::StringBundle::Service();
+    if (!bundleService) return false;
+
+    nsCOMPtr<nsIStringBundle> bundle;
+    rv = bundleService->CreateBundle(MAPI_PROPERTIES_CHROME,
+                                     getter_AddRefs(bundle));
+    if (NS_FAILED(rv) || !bundle) return false;
+
+    nsCOMPtr<nsIStringBundle> brandBundle;
+    rv =
+        bundleService->CreateBundle("chrome://branding/locale/brand.properties",
+                                    getter_AddRefs(brandBundle));
+    if (NS_FAILED(rv)) return false;
+
+    nsString brandName;
+    rv = brandBundle->GetStringFromName("brandFullName", brandName);
+    if (NS_FAILED(rv)) return false;
+
+    nsString loginTitle;
+    AutoTArray<nsString, 1> brandStrings = {brandName};
+    rv = bundle->FormatStringFromName("loginTitle", brandStrings, loginTitle);
+    if (NS_FAILED(rv)) return false;
+
+    if (aLogin) {
+      nsString loginText;
+      rv = bundle->GetStringFromName("loginTextwithName", loginText);
+      if (NS_FAILED(rv) || loginText.IsEmpty()) return false;
+
+      rv = dlgService->PromptUsernameAndPassword(nullptr, loginTitle.get(),
+                                                 loginText.get(), aUsername,
+                                                 aPassword, &btnResult);
+    } else {
+      // nsString loginString;
+      nsString loginText;
+      AutoTArray<nsString, 1> userNameStrings = {nsDependentString(*aUsername)};
+      rv =
+          bundle->FormatStringFromName("loginText", userNameStrings, loginText);
+      if (NS_FAILED(rv)) return false;
+
+      rv = dlgService->PromptPassword(nullptr, loginTitle.get(),
+                                      loginText.get(), aPassword, &btnResult);
+    }
+  }
+
+  return btnResult;
+}
+
+bool nsMapiHook::VerifyUserName(const nsCString& aUsername, nsCString& aIdKey) {
+  nsresult rv;
+
+  if (aUsername.IsEmpty()) return false;
+
+  nsCOMPtr<nsIMsgAccountManager> accountManager(
+      do_GetService("@mozilla.org/messenger/account-manager;1", &rv));
+  if (NS_FAILED(rv)) return false;
+  nsTArray<RefPtr<nsIMsgIdentity>> identities;
+  rv = accountManager->GetAllIdentities(identities);
+  if (NS_FAILED(rv)) return false;
+
+  for (auto thisIdentity : identities) {
+    if (thisIdentity) {
+      nsCString email;
+      rv = thisIdentity->GetEmail(email);
+      if (NS_FAILED(rv)) continue;
+
+      // get the username from the email and compare with the username
+      int32_t index = email.FindChar('@');
+      if (index != -1) email.SetLength(index);
+
+      if (aUsername.Equals(email))
+        return NS_SUCCEEDED(thisIdentity->GetKey(aIdKey));
+    }
+  }
+
+  return false;
+}
+
+bool nsMapiHook::IsBlindSendAllowed() {
+  bool enabled = false;
+  bool warn = true;
+  nsCOMPtr<nsIPrefBranch> prefBranch = do_GetService(NS_PREFSERVICE_CONTRACTID);
+  if (prefBranch) {
+    prefBranch->GetBoolPref(PREF_MAPI_WARN_PRIOR_TO_BLIND_SEND, &warn);
+    prefBranch->GetBoolPref(PREF_MAPI_BLIND_SEND_ENABLED, &enabled);
+  }
+  if (!enabled) return false;
+
+  if (!warn) return true;  // Everything is okay.
+
+  nsresult rv;
+  nsCOMPtr<nsIStringBundleService> bundleService =
+      mozilla::components::StringBundle::Service();
+  if (!bundleService) return false;
+
+  nsCOMPtr<nsIStringBundle> bundle;
+  rv = bundleService->CreateBundle(MAPI_PROPERTIES_CHROME,
+                                   getter_AddRefs(bundle));
+  if (NS_FAILED(rv) || !bundle) return false;
+
+  nsString warningMsg;
+  rv = bundle->GetStringFromName("mapiBlindSendWarning", warningMsg);
+  if (NS_FAILED(rv)) return false;
+
+  nsString dontShowAgainMessage;
+  rv = bundle->GetStringFromName("mapiBlindSendDontShowAgain",
+                                 dontShowAgainMessage);
+  if (NS_FAILED(rv)) return false;
+
+  nsCOMPtr<nsIPromptService> dlgService(
+      do_GetService(NS_PROMPTSERVICE_CONTRACTID, &rv));
+  if (NS_FAILED(rv) || !dlgService) return false;
+
+  bool continueToWarn = true;
+  bool okayToContinue = false;
+  dlgService->ConfirmCheck(nullptr, nullptr, warningMsg.get(),
+                           dontShowAgainMessage.get(), &continueToWarn,
+                           &okayToContinue);
+
+  if (!continueToWarn && okayToContinue && prefBranch)
+    prefBranch->SetBoolPref(PREF_MAPI_WARN_PRIOR_TO_BLIND_SEND, false);
+
+  return okayToContinue;
+}
+
+// this is used for Send without UI
+nsresult nsMapiHook::BlindSendMail(unsigned long aSession,
+                                   nsIMsgCompFields* aCompFields) {
+  nsresult rv = NS_OK;
+
+  if (!IsBlindSendAllowed()) return NS_ERROR_FAILURE;
+
+  // Get a hidden window to use for compose.
+  AutoHiddenWindow hiddenWindow(rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // smtp password and Logged in used IdKey from MapiConfig (session obj)
+  nsMAPIConfiguration* pMapiConfig =
+      nsMAPIConfiguration::GetMAPIConfiguration();
+  if (!pMapiConfig) return NS_ERROR_FAILURE;  // get the singleton obj
+  char16_t* password = pMapiConfig->GetPassword(aSession);
+
+  // Id key
+  nsCString MsgIdKey;
+  pMapiConfig->GetIdKey(aSession, MsgIdKey);
+
+  // get the MsgIdentity for the above key using AccountManager
+  nsCOMPtr<nsIMsgAccountManager> accountManager =
+      do_GetService("@mozilla.org/messenger/account-manager;1");
+  if (NS_FAILED(rv) || (!accountManager)) return rv;
+
+  nsCOMPtr<nsIMsgIdentity> pMsgId;
+  rv = accountManager->GetIdentity(MsgIdKey, getter_AddRefs(pMsgId));
+  if (NS_FAILED(rv)) return rv;
+
+  // create a send listener to get back the send status
+  RefPtr<MAPISendListener> sendListener = new MAPISendListener;
+
+  // create the compose params object
+  nsCOMPtr<nsIMsgComposeParams> pMsgComposeParams(
+      do_CreateInstance("@mozilla.org/messengercompose/composeparams;1", &rv));
+  if (NS_FAILED(rv) || (!pMsgComposeParams)) return rv;
+
+  // populate the compose params
+  bool forcePlainText;
+  aCompFields->GetForcePlainText(&forcePlainText);
+  pMsgComposeParams->SetType(nsIMsgCompType::New);
+  pMsgComposeParams->SetFormat(forcePlainText ? nsIMsgCompFormat::PlainText
+                                              : nsIMsgCompFormat::HTML);
+  pMsgComposeParams->SetIdentity(pMsgId);
+  pMsgComposeParams->SetComposeFields(aCompFields);
+  pMsgComposeParams->SetSendListener(sendListener);
+  if (password) pMsgComposeParams->SetSmtpPassword(nsDependentString(password));
+
+  // create the nsIMsgCompose object to send the object
+  nsCOMPtr<nsIMsgCompose> pMsgCompose(
+      do_CreateInstance("@mozilla.org/messengercompose/compose;1", &rv));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = pMsgCompose->Initialize(pMsgComposeParams, hiddenWindow, nullptr);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // If we're in offline mode, we'll need to queue it for later.
+  RefPtr<Promise> promise;
+  rv = pMsgCompose->SendMsg(WeAreOffline() ? nsIMsgSend::nsMsgQueueForLater
+                                           : nsIMsgSend::nsMsgDeliverNow,
+                            pMsgId, nullptr, nullptr, nullptr,
+                            getter_AddRefs(promise));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // When offline, the message is saved to Outbox and OnStopSending won't be
+  // called.
+  if (WeAreOffline()) return NS_OK;
+
+  // Wait for OnStopSending to be called.
+  mozilla::SpinEventLoopUntil("nsIMsgCompose::SendMsg is async"_ns,
+                              [=]() { return sendListener->IsDone(); });
+
+  return rv;
+}
+
+nsresult nsMapiHook::HandleAttachments(nsIMsgCompFields* aCompFields,
+                                       int32_t aFileCount,
+                                       lpnsMapiFileDesc aFiles, bool aIsUTF8) {
+  nsresult rv = NS_OK;
+  // Do nothing if there are no files to process.
+  if (!aFiles || aFileCount <= 0) return NS_OK;
+
+  nsAutoCString Attachments;
+  nsAutoCString TempFiles;
+
+  nsCOMPtr<nsIFile> pFile = do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv);
+  if (NS_FAILED(rv) || (!pFile)) return rv;
+  nsCOMPtr<nsIFile> pTempDir = do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv);
+  if (NS_FAILED(rv) || (!pTempDir)) return rv;
+
+  for (int i = 0; i < aFileCount; i++) {
+    if (aFiles[i].lpszPathName) {
+      // check if attachment exists
+      if (!aIsUTF8)
+        pFile->InitWithNativePath(nsDependentCString(aFiles[i].lpszPathName));
+      else
+        pFile->InitWithPath(NS_ConvertUTF8toUTF16(aFiles[i].lpszPathName));
+
+      bool bExist;
+      rv = pFile->Exists(&bExist);
+      MOZ_LOG(
+          MAPI, mozilla::LogLevel::Debug,
+          ("nsMapiHook::HandleAttachments: filename: %s path: %s exists = %s\n",
+           (const char*)aFiles[i].lpszFileName,
+           (const char*)aFiles[i].lpszPathName, bExist ? "true" : "false"));
+      if (NS_FAILED(rv) || (!bExist)) return NS_ERROR_FILE_NOT_FOUND;
+
+      // Temp Directory
+      nsCOMPtr<nsIFile> pTempDir;
+      NS_GetSpecialDirectory(NS_OS_TEMP_DIR, getter_AddRefs(pTempDir));
+
+      // create a new sub directory called moz_mapi underneath the temp
+      // directory
+      pTempDir->AppendRelativePath(u"moz_mapi"_ns);
+      pTempDir->Exists(&bExist);
+      if (!bExist) {
+        rv = pTempDir->Create(nsIFile::DIRECTORY_TYPE, 777);
+        if (NS_FAILED(rv)) return rv;
+      }
+
+      // rename or copy the existing temp file with the real file name
+
+      nsAutoString leafName;
+      // convert to Unicode using Platform charset
+      // leafName already contains a unicode leafName from lpszPathName. If we
+      // were given a value for lpszFileName, use it. Otherwise stick with
+      // leafName
+      if (aFiles[i].lpszFileName) {
+        nsAutoString wholeFileName;
+        if (!aIsUTF8)
+          NS_CopyNativeToUnicode(nsDependentCString(aFiles[i].lpszFileName),
+                                 wholeFileName);
+        else
+          wholeFileName.Append(NS_ConvertUTF8toUTF16(aFiles[i].lpszFileName));
+        // need to find the last '\' and find the leafname from that.
+        int32_t lastSlash = wholeFileName.RFindChar(char16_t('\\'));
+        if (lastSlash != kNotFound)
+          leafName.Assign(Substring(wholeFileName, lastSlash + 1));
+        else
+          leafName.Assign(wholeFileName);
+      } else
+        pFile->GetLeafName(leafName);
+
+      nsCOMPtr<nsIMsgAttachment> attachment =
+          do_CreateInstance("@mozilla.org/messengercompose/attachment;1", &rv);
+      NS_ENSURE_SUCCESS(rv, rv);
+      attachment->SetName(leafName);
+
+      nsCOMPtr<nsIFile> pTempFile;
+      rv = pTempDir->Clone(getter_AddRefs(pTempFile));
+      if (NS_FAILED(rv) || !pTempFile) return rv;
+
+      pTempFile->Append(leafName);
+      pTempFile->Exists(&bExist);
+      if (bExist) {
+        rv = pTempFile->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0777);
+        NS_ENSURE_SUCCESS(rv, rv);
+        pTempFile->Remove(false);  // remove so we can copy over it.
+        pTempFile->GetLeafName(leafName);
+      }
+      // copy the file to its new location and file name
+      pFile->CopyTo(pTempDir, leafName);
+      // point pFile to the new location of the attachment
+      pFile->InitWithFile(pTempDir);
+      pFile->Append(leafName);
+
+      // create MsgCompose attachment object
+      attachment->SetTemporary(
+          true);  // this one is a temp file so set the flag for MsgCompose
+
+      // now set the attachment object
+      nsAutoCString pURL;
+      NS_GetURLSpecFromFile(pFile, pURL);
+      attachment->SetUrl(pURL);
+
+      // set the file size
+      int64_t fileSize;
+      pFile->GetFileSize(&fileSize);
+      attachment->SetSize(fileSize);
+
+      // add the attachment
+      rv = aCompFields->AddAttachment(attachment);
+      if (NS_FAILED(rv))
+        MOZ_LOG(
+            MAPI, mozilla::LogLevel::Debug,
+            ("nsMapiHook::HandleAttachments: AddAttachment rv =  %x\n", rv));
+    }
+  }
+  return rv;
+}
+
+nsresult nsMapiHook::HandleAttachmentsW(nsIMsgCompFields* aCompFields,
+                                        int32_t aFileCount,
+                                        lpnsMapiFileDescW aFiles) {
+  nsresult rv = NS_OK;
+  // Do nothing if there are no files to process.
+  if (!aFiles || aFileCount <= 0) return NS_OK;
+
+  nsAutoCString Attachments;
+  nsAutoCString TempFiles;
+
+  nsCOMPtr<nsIFile> pFile = do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv);
+  if (NS_FAILED(rv) || (!pFile)) return rv;
+  nsCOMPtr<nsIFile> pTempDir = do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv);
+  if (NS_FAILED(rv) || (!pTempDir)) return rv;
+
+  for (int i = 0; i < aFileCount; i++) {
+    if (aFiles[i].lpszPathName) {
+      // Check if attachment exists.
+      pFile->InitWithPath(nsDependentString(aFiles[i].lpszPathName));
+
+      bool bExist;
+      rv = pFile->Exists(&bExist);
+      MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+              ("nsMapiHook::HandleAttachmentsW: filename: %s path: %s exists = "
+               "%s \n",
+               NS_ConvertUTF16toUTF8(aFiles[i].lpszFileName).get(),
+               NS_ConvertUTF16toUTF8(aFiles[i].lpszPathName).get(),
+               bExist ? "true" : "false"));
+      if (NS_FAILED(rv) || (!bExist)) return NS_ERROR_FILE_NOT_FOUND;
+
+      // Temp Directory.
+      nsCOMPtr<nsIFile> pTempDir;
+      NS_GetSpecialDirectory(NS_OS_TEMP_DIR, getter_AddRefs(pTempDir));
+
+      // Create a new sub directory called moz_mapi underneath the temp
+      // directory.
+      pTempDir->AppendRelativePath(u"moz_mapi"_ns);
+      pTempDir->Exists(&bExist);
+      if (!bExist) {
+        rv = pTempDir->Create(nsIFile::DIRECTORY_TYPE, 777);
+        if (NS_FAILED(rv)) return rv;
+      }
+
+      // Rename or copy the existing temp file with the real file name.
+
+      nsAutoString leafName;
+      // leafName already contains a unicode leafName from lpszPathName. If we
+      // were given a value for lpszFileName, use it. Otherwise stick with
+      // leafName.
+      if (aFiles[i].lpszFileName) {
+        nsAutoString wholeFileName(aFiles[i].lpszFileName);
+        // Need to find the last '\' and find the leafname from that.
+        int32_t lastSlash = wholeFileName.RFindChar(char16_t('\\'));
+        if (lastSlash != kNotFound)
+          leafName.Assign(Substring(wholeFileName, lastSlash + 1));
+        else
+          leafName.Assign(wholeFileName);
+      } else
+        pFile->GetLeafName(leafName);
+
+      nsCOMPtr<nsIMsgAttachment> attachment =
+          do_CreateInstance("@mozilla.org/messengercompose/attachment;1", &rv);
+      NS_ENSURE_SUCCESS(rv, rv);
+      attachment->SetName(leafName);
+
+      nsCOMPtr<nsIFile> pTempFile;
+      rv = pTempDir->Clone(getter_AddRefs(pTempFile));
+      if (NS_FAILED(rv) || !pTempFile) return rv;
+
+      pTempFile->Append(leafName);
+      pTempFile->Exists(&bExist);
+      if (bExist) {
+        rv = pTempFile->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0777);
+        NS_ENSURE_SUCCESS(rv, rv);
+        pTempFile->Remove(false);  // remove so we can copy over it.
+        pTempFile->GetLeafName(leafName);
+      }
+      // Copy the file to its new location and file name.
+      pFile->CopyTo(pTempDir, leafName);
+      // Point pFile to the new location of the attachment.
+      pFile->InitWithFile(pTempDir);
+      pFile->Append(leafName);
+
+      // Create MsgCompose attachment object.
+      attachment->SetTemporary(
+          true);  // this one is a temp file so set the flag for MsgCompose
+
+      // Now set the attachment object.
+      nsAutoCString pURL;
+      NS_GetURLSpecFromFile(pFile, pURL);
+      attachment->SetUrl(pURL);
+
+      // Set the file size.
+      int64_t fileSize;
+      pFile->GetFileSize(&fileSize);
+      attachment->SetSize(fileSize);
+
+      // Add the attachment.
+      rv = aCompFields->AddAttachment(attachment);
+      if (NS_FAILED(rv))
+        MOZ_LOG(
+            MAPI, mozilla::LogLevel::Debug,
+            ("nsMapiHook::HandleAttachmentsW: AddAttachment rv =  %x\n", rv));
+    }
+  }
+  return rv;
+}
+
+// this is used to convert non Unicode data and then populate comp fields
+nsresult nsMapiHook::PopulateCompFieldsWithConversion(
+    lpnsMapiMessage aMessage, nsIMsgCompFields* aCompFields) {
+  bool isUTF8 = aMessage->ulReserved == CP_UTF8;
+
+  if (aMessage->lpOriginator && aMessage->lpOriginator->lpszAddress) {
+    nsAutoString From;
+    if (!isUTF8)
+      From.Append(NS_ConvertASCIItoUTF16(aMessage->lpOriginator->lpszAddress));
+    else
+      From.Append(NS_ConvertUTF8toUTF16(aMessage->lpOriginator->lpszAddress));
+    aCompFields->SetFrom(From);
+  }
+
+  nsAutoString To;
+  nsAutoString Cc;
+  nsAutoString Bcc;
+  constexpr auto Comma = u","_ns;
+  if (aMessage->lpRecips) {
+    for (int i = 0; i < (int)aMessage->nRecipCount; i++) {
+      if (aMessage->lpRecips[i].lpszAddress || aMessage->lpRecips[i].lpszName) {
+        const char* addressWithoutType = (aMessage->lpRecips[i].lpszAddress)
+                                             ? aMessage->lpRecips[i].lpszAddress
+                                             : aMessage->lpRecips[i].lpszName;
+        if (!PL_strncasecmp(addressWithoutType, "SMTP:", 5))
+          addressWithoutType += 5;
+
+        switch (aMessage->lpRecips[i].ulRecipClass) {
+          case MAPI_TO:
+            if (!To.IsEmpty()) To += Comma;
+            if (!isUTF8)
+              To.Append(NS_ConvertASCIItoUTF16(addressWithoutType));
+            else
+              To.Append(NS_ConvertUTF8toUTF16(addressWithoutType));
+            break;
+
+          case MAPI_CC:
+            if (!Cc.IsEmpty()) Cc += Comma;
+            if (!isUTF8)
+              Cc.Append(NS_ConvertASCIItoUTF16(addressWithoutType));
+            else
+              Cc.Append(NS_ConvertUTF8toUTF16(addressWithoutType));
+            break;
+
+          case MAPI_BCC:
+            if (!Bcc.IsEmpty()) Bcc += Comma;
+            if (!isUTF8)
+              Bcc.Append(NS_ConvertASCIItoUTF16(addressWithoutType));
+            else
+              Bcc.Append(NS_ConvertUTF8toUTF16(addressWithoutType));
+            break;
+        }
+      }
+    }
+  }
+
+  // set To, Cc, Bcc
+  aCompFields->SetTo(To);
+  aCompFields->SetCc(Cc);
+  aCompFields->SetBcc(Bcc);
+
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("to: %s cc: %s bcc: %s \n", NS_ConvertUTF16toUTF8(To).get(),
+           NS_ConvertUTF16toUTF8(Cc).get(), NS_ConvertUTF16toUTF8(Bcc).get()));
+
+  // set subject
+  nsresult rv = NS_OK;
+  if (aMessage->lpszSubject) {
+    nsAutoString Subject;
+    if (!isUTF8)
+      rv = NS_CopyNativeToUnicode(nsDependentCString(aMessage->lpszSubject),
+                                  Subject);
+    else
+      Subject.Append(NS_ConvertUTF8toUTF16(aMessage->lpszSubject));
+    if (NS_FAILED(rv)) return rv;
+    aCompFields->SetSubject(Subject);
+  }
+
+  // handle attachments as File URL
+  rv = HandleAttachments(aCompFields, aMessage->nFileCount, aMessage->lpFiles,
+                         isUTF8);
+  if (NS_FAILED(rv)) return rv;
+
+  // set body
+  if (aMessage->lpszNoteText) {
+    nsAutoString Body;
+    if (!isUTF8)
+      rv = NS_CopyNativeToUnicode(nsDependentCString(aMessage->lpszNoteText),
+                                  Body);
+    else
+      Body.Append(NS_ConvertUTF8toUTF16(aMessage->lpszNoteText));
+    if (NS_FAILED(rv)) return rv;
+    if (Body.IsEmpty() || Body.Last() != '\n') Body.AppendLiteral(CRLF);
+
+    // This is needed when Simple MAPI is used without a compose window.
+    // See bug 1366196.
+    if (Body.Find(u"<html>") == kNotFound) aCompFields->SetForcePlainText(true);
+
+    rv = aCompFields->SetBody(Body);
+  } else {
+    // No body: Assume that we can do plaintext. This will trigger the default
+    // compose format in ShowComposerWindow().
+    aCompFields->SetForcePlainText(true);
+  }
+
+#ifdef RAJIV_DEBUG
+  // testing what all was set in CompFields
+  printf("To : %S \n", To.get());
+  printf("CC : %S \n", Cc.get());
+  printf("BCC : %S \n", Bcc.get());
+#endif
+
+  return rv;
+}
+
+// This is used to populate comp fields with UTF-16 data from MAPISendMailW
+// function.
+nsresult nsMapiHook::PopulateCompFieldsW(lpnsMapiMessageW aMessage,
+                                         nsIMsgCompFields* aCompFields) {
+  if (aMessage->lpOriginator && aMessage->lpOriginator->lpszAddress)
+    aCompFields->SetFrom(
+        nsDependentString(aMessage->lpOriginator->lpszAddress));
+
+  nsAutoString To;
+  nsAutoString Cc;
+  nsAutoString Bcc;
+
+  constexpr auto Comma = u","_ns;
+
+  if (aMessage->lpRecips) {
+    for (int i = 0; i < (int)aMessage->nRecipCount; i++) {
+      if (aMessage->lpRecips[i].lpszAddress || aMessage->lpRecips[i].lpszName) {
+        const wchar_t* addressWithoutType =
+            (aMessage->lpRecips[i].lpszAddress)
+                ? aMessage->lpRecips[i].lpszAddress
+                : aMessage->lpRecips[i].lpszName;
+        if (_wcsnicmp(addressWithoutType, L"SMTP:", 5) == 0)
+          addressWithoutType += 5;
+        switch (aMessage->lpRecips[i].ulRecipClass) {
+          case MAPI_TO:
+            if (!To.IsEmpty()) To += Comma;
+            To.Append(nsDependentString(addressWithoutType));
+            break;
+
+          case MAPI_CC:
+            if (!Cc.IsEmpty()) Cc += Comma;
+            Cc.Append(nsDependentString(addressWithoutType));
+            break;
+
+          case MAPI_BCC:
+            if (!Bcc.IsEmpty()) Bcc += Comma;
+            Bcc.Append(nsDependentString(addressWithoutType));
+            break;
+        }
+      }
+    }
+  }
+
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("to: %s cc: %s bcc: %s \n", NS_ConvertUTF16toUTF8(To).get(),
+           NS_ConvertUTF16toUTF8(Cc).get(), NS_ConvertUTF16toUTF8(Bcc).get()));
+  // set To, Cc, Bcc
+  aCompFields->SetTo(To);
+  aCompFields->SetCc(Cc);
+  aCompFields->SetBcc(Bcc);
+
+  // Set subject.
+  if (aMessage->lpszSubject)
+    aCompFields->SetSubject(nsDependentString(aMessage->lpszSubject));
+
+  // handle attachments as File URL
+  nsresult rv =
+      HandleAttachmentsW(aCompFields, aMessage->nFileCount, aMessage->lpFiles);
+  if (NS_FAILED(rv)) return rv;
+
+  // Set body.
+  if (aMessage->lpszNoteText) {
+    nsString Body(aMessage->lpszNoteText);
+    if (Body.IsEmpty() || Body.Last() != '\n') Body.AppendLiteral(CRLF);
+
+    // This is needed when Simple MAPI is used without a compose window.
+    // See bug 1366196.
+    if (Body.Find(u"<html>") == kNotFound) aCompFields->SetForcePlainText(true);
+
+    rv = aCompFields->SetBody(Body);
+  } else {
+    // No body: Assume that we can do plaintext. This will trigger the default
+    // compose format in ShowComposerWindow().
+    aCompFields->SetForcePlainText(true);
+  }
+  return rv;
+}
+
+// this is used to populate the docs as attachments in the Comp fields for Send
+// Documents
+nsresult nsMapiHook::PopulateCompFieldsForSendDocs(
+    nsIMsgCompFields* aCompFields, ULONG aFlags, LPSTR aDelimChar,
+    LPSTR aFilePaths) {
+  nsAutoCString strDelimChars;
+  nsAutoCString strFilePaths;
+  nsresult rv = NS_OK;
+  bool bExist;
+
+  if (aDelimChar) strDelimChars.Assign(aDelimChar);
+  if (aFilePaths) strFilePaths.Assign(aFilePaths);
+
+  // check for comma in filename
+  if (strDelimChars.FindChar(',') ==
+      kNotFound)  // if comma is not in the delimiter specified by user
+  {
+    if (strFilePaths.FindChar(',') !=
+        kNotFound)  // if comma found in filenames return error
+      return NS_ERROR_FILE_INVALID_PATH;
+  }
+
+  nsCString Attachments;
+
+  // only 1 file is to be sent, no delim specified
+  if (strDelimChars.IsEmpty()) strDelimChars.Assign(';');
+
+  int32_t offset = 0;
+  int32_t FilePathsLen = strFilePaths.Length();
+  if (FilePathsLen) {
+    nsAutoString Subject;
+
+    // multiple files to be sent, delim specified
+    nsCOMPtr<nsIFile> pFile = do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv);
+    if (NS_FAILED(rv) || (!pFile)) return rv;
+
+    char* newFilePaths = (char*)strFilePaths.get();
+    while (offset != kNotFound) {
+      // Temp Directory
+      nsCOMPtr<nsIFile> pTempDir;
+      NS_GetSpecialDirectory(NS_OS_TEMP_DIR, getter_AddRefs(pTempDir));
+
+      // if not already existing, create another temp dir for mapi within Win
+      // temp dir this is windows only so we can do "\\"
+      pTempDir->AppendRelativePath(u"moz_mapi"_ns);
+      pTempDir->Exists(&bExist);
+      if (!bExist) {
+        rv = pTempDir->Create(nsIFile::DIRECTORY_TYPE, 777);
+        if (NS_FAILED(rv)) return rv;
+      }
+
+      nsAutoCString RemainingPaths;
+      RemainingPaths.Assign(newFilePaths);
+      offset = RemainingPaths.Find(strDelimChars);
+      if (offset != kNotFound) {
+        RemainingPaths.SetLength(offset);
+        if ((offset + (int32_t)strDelimChars.Length()) < FilePathsLen)
+          newFilePaths += offset + strDelimChars.Length();
+        else
+          offset = kNotFound;
+        FilePathsLen -= offset + strDelimChars.Length();
+      }
+
+      if (RemainingPaths[1] != ':' && RemainingPaths[1] != '\\') {
+        char cwd[MAX_PATH];
+        if (_getdcwd(_getdrive(), cwd, MAX_PATH)) {
+          nsAutoCString cwdStr;
+          cwdStr.Assign(cwd);
+          cwdStr.Append('\\');
+          RemainingPaths.Insert(cwdStr, 0);
+        }
+      }
+
+      pFile->InitWithNativePath(RemainingPaths);
+
+      rv = pFile->Exists(&bExist);
+      if (NS_FAILED(rv) || (!bExist)) return NS_ERROR_FILE_NOT_FOUND;
+
+      // filename of the file attachment
+      nsAutoString leafName;
+      pFile->GetLeafName(leafName);
+      if (NS_FAILED(rv) || leafName.IsEmpty()) return rv;
+
+      if (!Subject.IsEmpty()) Subject.AppendLiteral(", ");
+      Subject += leafName;
+
+      // create MsgCompose attachment object
+      nsCOMPtr<nsIMsgAttachment> attachment =
+          do_CreateInstance("@mozilla.org/messengercompose/attachment;1", &rv);
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      nsDependentString fileNameNative(leafName.get());
+      rv = pFile->CopyTo(pTempDir, fileNameNative);
+      if (NS_FAILED(rv)) return rv;
+
+      // now turn pTempDir into a full file path to the temp file
+      pTempDir->Append(fileNameNative);
+
+      // this one is a temp file so set the flag for MsgCompose
+      attachment->SetTemporary(true);
+
+      // now set the attachment object
+      nsAutoCString pURL;
+      NS_GetURLSpecFromFile(pTempDir, pURL);
+      attachment->SetUrl(pURL);
+
+      // set the file size
+      int64_t fileSize;
+      pFile->GetFileSize(&fileSize);
+      attachment->SetSize(fileSize);
+
+      // add the attachment
+      rv = aCompFields->AddAttachment(attachment);
+      if (NS_FAILED(rv)) return rv;
+    }
+
+    rv = aCompFields->SetBody(Subject);
+  }
+
+  return rv;
+}
+
+// this used for Send with UI
+nsresult nsMapiHook::ShowComposerWindow(unsigned long aSession,
+                                        nsIMsgCompFields* aCompFields) {
+  nsresult rv = NS_OK;
+
+  // create a send listener to get back the send status
+  RefPtr<MAPISendListener> sendListener = new MAPISendListener;
+
+  // create the compose params object
+  nsCOMPtr<nsIMsgComposeParams> pMsgComposeParams(
+      do_CreateInstance("@mozilla.org/messengercompose/composeparams;1", &rv));
+  if (NS_FAILED(rv) || (!pMsgComposeParams)) return rv;
+
+  // If we found HTML, compose in HTML.
+  bool forcePlainText;
+  aCompFields->GetForcePlainText(&forcePlainText);
+  pMsgComposeParams->SetFormat(forcePlainText ? nsIMsgCompFormat::Default
+                                              : nsIMsgCompFormat::HTML);
+
+  // populate the compose params
+  pMsgComposeParams->SetType(nsIMsgCompType::New);
+
+  // Never force to plain text, the default format will take care of that.
+  // Undo the forcing that happened in
+  // PopulateCompFields/PopulateCompFieldsWithConversion. See bug 1095629 and
+  // bug 1366196.
+  aCompFields->SetForcePlainText(false);
+  pMsgComposeParams->SetComposeFields(aCompFields);
+  pMsgComposeParams->SetSendListener(sendListener);
+
+  /** get the nsIMsgComposeService object to open the compose window **/
+  nsCOMPtr<nsIMsgComposeService> compService =
+      do_GetService("@mozilla.org/messengercompose;1");
+  if (NS_FAILED(rv) || (!compService)) return rv;
+
+  rv = compService->OpenComposeWindowWithParams(nullptr, pMsgComposeParams);
+  if (NS_FAILED(rv)) return rv;
+
+  return rv;
+}
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiHook.h b/comm/mailnews/mapi/mapihook/src/msgMapiHook.h
new file mode 100644
index 0000000000..aa6ad1d66f
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiHook.h
@@ -0,0 +1,39 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MSG_MAPI_HOOK_H_
+#define MSG_MAPI_HOOK_H_
+
+#include "prtypes.h"
+
+class nsMapiHook {
+ public:
+  static bool DisplayLoginDialog(bool aLogin, char16_t** aUsername,
+                                 char16_t** aPassword);
+  static bool VerifyUserName(const nsCString& aUsername, nsCString& aIdKey);
+
+  static bool IsBlindSendAllowed();
+  static nsresult BlindSendMail(unsigned long aSession,
+                                nsIMsgCompFields* aCompFields);
+  static nsresult ShowComposerWindow(unsigned long aSession,
+                                     nsIMsgCompFields* aCompFields);
+  static nsresult PopulateCompFieldsWithConversion(
+      lpnsMapiMessage aMessage, nsIMsgCompFields* aCompFields);
+  static nsresult PopulateCompFieldsW(lpnsMapiMessageW aMessage,
+                                      nsIMsgCompFields* aCompFields);
+  static nsresult PopulateCompFieldsForSendDocs(nsIMsgCompFields* aCompFields,
+                                                ULONG aFlags, LPSTR aDelimChar,
+                                                LPSTR aFilePaths);
+  static nsresult HandleAttachments(nsIMsgCompFields* aCompFields,
+                                    int32_t aFileCount, lpnsMapiFileDesc aFiles,
+                                    bool aIsUTF8);
+  static nsresult HandleAttachmentsW(nsIMsgCompFields* aCompFields,
+                                     int32_t aFileCount,
+                                     lpnsMapiFileDescW aFiles);
+  static void CleanUp();
+
+  static bool isMapiService;
+};
+
+#endif  // MSG_MAPI_HOOK_H_
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiImp.cpp b/comm/mailnews/mapi/mapihook/src/msgMapiImp.cpp
new file mode 100644
index 0000000000..62abed1f7b
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiImp.cpp
@@ -0,0 +1,801 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <mapidefs.h>
+#include <mapi.h>
+#include <winstring.h>
+#include "msgMapiImp.h"
+#include "msgMapiFactory.h"
+#include "msgMapiMain.h"
+
+#include "nsIMsgCompFields.h"
+#include "msgMapiHook.h"
+#include "nsString.h"
+#include "nsCOMPtr.h"
+#include "nsISupports.h"
+#include "nsIMsgDatabase.h"
+#include "nsMsgFolderFlags.h"
+#include "nsIMsgHdr.h"
+#include "MailNewsTypes.h"
+#include "nsIMsgAccountManager.h"
+#include "nsIMsgFolder.h"
+#include "nsIMsgImapMailFolder.h"
+#include <time.h>
+#include "nsIInputStream.h"
+#include "nsILineInputStream.h"
+#include "nsISeekableStream.h"
+#include "nsIFile.h"
+#include "nsIFileStreams.h"
+#include "nsNetCID.h"
+#include "nsMsgMessageFlags.h"
+#include "mozilla/mailnews/MimeHeaderParser.h"
+#include "mozilla/Logging.h"
+
+using namespace mozilla::mailnews;
+
+mozilla::LazyLogModule MAPI("MAPI");
+
+CMapiImp::CMapiImp() : m_cRef(1) { m_Lock = PR_NewLock(); }
+
+CMapiImp::~CMapiImp() {
+  if (m_Lock) PR_DestroyLock(m_Lock);
+}
+
+STDMETHODIMP CMapiImp::QueryInterface(const IID& aIid, void** aPpv) {
+  if (aIid == IID_IUnknown) {
+    *aPpv = static_cast<nsIMapi*>(this);
+  } else if (aIid == IID_nsIMapi) {
+    *aPpv = static_cast<nsIMapi*>(this);
+  } else {
+    *aPpv = nullptr;
+    return E_NOINTERFACE;
+  }
+
+  reinterpret_cast<IUnknown*>(*aPpv)->AddRef();
+  return S_OK;
+}
+
+STDMETHODIMP_(ULONG) CMapiImp::AddRef() { return ++m_cRef; }
+
+STDMETHODIMP_(ULONG) CMapiImp::Release() {
+  int32_t temp = --m_cRef;
+  if (m_cRef == 0) {
+    delete this;
+    return 0;
+  }
+
+  return temp;
+}
+
+STDMETHODIMP CMapiImp::IsValid() { return S_OK; }
+
+STDMETHODIMP CMapiImp::IsValidSession(unsigned long aSession) {
+  nsMAPIConfiguration* pConfig = nsMAPIConfiguration::GetMAPIConfiguration();
+  if (pConfig && pConfig->IsSessionValid(aSession)) return S_OK;
+
+  return E_FAIL;
+}
+
+STDMETHODIMP CMapiImp::Initialize() {
+  HRESULT hr = E_FAIL;
+
+  if (!m_Lock) return E_FAIL;
+
+  PR_Lock(m_Lock);
+
+  // Initialize MAPI Configuration
+
+  nsMAPIConfiguration* pConfig = nsMAPIConfiguration::GetMAPIConfiguration();
+  if (pConfig != nullptr) hr = S_OK;
+
+  PR_Unlock(m_Lock);
+
+  return hr;
+}
+
+STDMETHODIMP CMapiImp::Login(unsigned long aUIArg, LPSTR aLogin,
+                             LPSTR aPassWord, unsigned long aFlags,
+                             unsigned long* aSessionId) {
+  HRESULT hr = E_FAIL;
+  bool bNewSession = false;
+  nsCString id_key;
+
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("CMapiImp::Login using flags %lu", aFlags));
+  if (aFlags & MAPI_NEW_SESSION) bNewSession = true;
+
+  // Check For Profile Name
+  if (aLogin != nullptr && aLogin[0] != '\0') {
+    if (!nsMapiHook::VerifyUserName(nsDependentCString(aLogin), id_key)) {
+      *aSessionId = MAPI_E_LOGIN_FAILURE;
+      MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+              ("CMapiImp::Login failed for username %s", aLogin));
+      NS_ASSERTION(false, "failed verifying user name");
+      return hr;
+    }
+  } else {
+    // get default account
+    nsresult rv;
+    nsCOMPtr<nsIMsgAccountManager> accountManager =
+        do_GetService("@mozilla.org/messenger/account-manager;1", &rv);
+    NS_ENSURE_SUCCESS(rv, MAPI_E_LOGIN_FAILURE);
+
+    nsCOMPtr<nsIMsgAccount> account;
+    rv = accountManager->GetDefaultAccount(getter_AddRefs(account));
+    NS_ENSURE_SUCCESS(rv, MAPI_E_LOGIN_FAILURE);
+    if (!account) return MAPI_E_LOGIN_FAILURE;
+
+    nsCOMPtr<nsIMsgIdentity> identity;
+    rv = account->GetDefaultIdentity(getter_AddRefs(identity));
+    NS_ENSURE_SUCCESS(rv, MAPI_E_LOGIN_FAILURE);
+    if (!identity) return MAPI_E_LOGIN_FAILURE;
+    identity->GetKey(id_key);
+  }
+
+  // finally register(create) the session.
+  uint32_t nSession_Id;
+  int16_t nResult = 0;
+
+  nsMAPIConfiguration* pConfig = nsMAPIConfiguration::GetMAPIConfiguration();
+  if (pConfig != nullptr)
+    nResult = pConfig->RegisterSession(
+        aUIArg, aLogin ? nsDependentCString(aLogin) : EmptyCString(),
+        aPassWord ? nsDependentCString(aPassWord) : EmptyCString(),
+        (aFlags & MAPI_FORCE_DOWNLOAD), bNewSession, &nSession_Id,
+        id_key.get());
+  switch (nResult) {
+    case -1: {
+      *aSessionId = MAPI_E_TOO_MANY_SESSIONS;
+      return hr;
+    }
+    case 0: {
+      *aSessionId = MAPI_E_INSUFFICIENT_MEMORY;
+      return hr;
+    }
+    default: {
+      *aSessionId = nSession_Id;
+      MOZ_LOG(MAPI, mozilla::LogLevel::Debug, ("CMapiImp::Login succeeded"));
+      break;
+    }
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP CMapiImp::SendMail(unsigned long aSession,
+                                lpnsMapiMessage aMessage, unsigned long aFlags,
+                                unsigned long aReserved) {
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("CMapiImp::SendMail flags=%lx subject: %s sender: %s", aFlags,
+           (aMessage && aMessage->lpszSubject) ? aMessage->lpszSubject
+                                               : "(no subject)",
+           (aMessage && aMessage->lpOriginator &&
+            aMessage->lpOriginator->lpszAddress)
+               ? aMessage->lpOriginator->lpszAddress
+               : "(no sender)"));
+
+  /** create nsIMsgCompFields obj and populate it **/
+  nsresult rv = NS_OK;
+  nsCOMPtr<nsIMsgCompFields> pCompFields =
+      do_CreateInstance("@mozilla.org/messengercompose/composefields;1", &rv);
+  if (NS_FAILED(rv) || (!pCompFields)) return MAPI_E_INSUFFICIENT_MEMORY;
+
+  if (aMessage)
+    rv = nsMapiHook::PopulateCompFieldsWithConversion(aMessage, pCompFields);
+
+  if (NS_SUCCEEDED(rv)) {
+    // see flag to see if UI needs to be brought up
+    if (!(aFlags & MAPI_DIALOG)) {
+      rv = nsMapiHook::BlindSendMail(aSession, pCompFields);
+    } else {
+      rv = nsMapiHook::ShowComposerWindow(aSession, pCompFields);
+    }
+  }
+
+  return nsMAPIConfiguration::GetMAPIErrorFromNSError(rv);
+}
+
+STDMETHODIMP CMapiImp::SendMailW(unsigned long aSession,
+                                 lpnsMapiMessageW aMessage,
+                                 unsigned long aFlags,
+                                 unsigned long aReserved) {
+  MOZ_LOG(
+      MAPI, mozilla::LogLevel::Debug,
+      ("CMapiImp::SendMailW flags=%lx subject: %s sender: %s", aFlags,
+       (aMessage && aMessage->lpszSubject)
+           ? NS_ConvertUTF16toUTF8(aMessage->lpszSubject).get()
+           : "(no subject)",
+       (aMessage && aMessage->lpOriginator &&
+        aMessage->lpOriginator->lpszAddress)
+           ? NS_ConvertUTF16toUTF8(aMessage->lpOriginator->lpszAddress).get()
+           : "(no sender)"));
+
+  // Create nsIMsgCompFields obj and populate it.
+  nsresult rv = NS_OK;
+  nsCOMPtr<nsIMsgCompFields> pCompFields =
+      do_CreateInstance("@mozilla.org/messengercompose/composefields;1", &rv);
+  if (NS_FAILED(rv) || !pCompFields) return MAPI_E_INSUFFICIENT_MEMORY;
+
+  if (aMessage) rv = nsMapiHook::PopulateCompFieldsW(aMessage, pCompFields);
+
+  if (NS_SUCCEEDED(rv)) {
+    // Check flag to see if UI needs to be brought up.
+    if (!(aFlags & MAPI_DIALOG)) {
+      rv = nsMapiHook::BlindSendMail(aSession, pCompFields);
+    } else {
+      rv = nsMapiHook::ShowComposerWindow(aSession, pCompFields);
+    }
+  }
+
+  return nsMAPIConfiguration::GetMAPIErrorFromNSError(rv);
+}
+
+STDMETHODIMP CMapiImp::SendDocuments(unsigned long aSession, LPSTR aDelimChar,
+                                     LPSTR aFilePaths, LPSTR aFileNames,
+                                     ULONG aFlags) {
+  nsresult rv = NS_OK;
+
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("CMapiImp::SendDocument using flags %lu", aFlags));
+  /** create nsIMsgCompFields obj and populate it **/
+  nsCOMPtr<nsIMsgCompFields> pCompFields =
+      do_CreateInstance("@mozilla.org/messengercompose/composefields;1", &rv);
+  if (NS_FAILED(rv) || (!pCompFields)) return MAPI_E_INSUFFICIENT_MEMORY;
+
+  if (aFilePaths) {
+    rv = nsMapiHook::PopulateCompFieldsForSendDocs(pCompFields, aFlags,
+                                                   aDelimChar, aFilePaths);
+  }
+
+  if (NS_SUCCEEDED(rv))
+    rv = nsMapiHook::ShowComposerWindow(aSession, pCompFields);
+  else
+    MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+            ("CMapiImp::SendDocument error rv = %x, paths = %s names = %s", rv,
+             aFilePaths, aFileNames));
+
+  return nsMAPIConfiguration::GetMAPIErrorFromNSError(rv);
+}
+
+nsresult CMapiImp::GetDefaultInbox(nsIMsgFolder** inboxFolder) {
+  // get default account
+  nsresult rv;
+  nsCOMPtr<nsIMsgAccountManager> accountManager =
+      do_GetService("@mozilla.org/messenger/account-manager;1", &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIMsgAccount> account;
+  rv = accountManager->GetDefaultAccount(getter_AddRefs(account));
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!account) return NS_ERROR_FAILURE;
+
+  // get incoming server
+  nsCOMPtr<nsIMsgIncomingServer> server;
+  rv = account->GetIncomingServer(getter_AddRefs(server));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCString type;
+  rv = server->GetType(type);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // we only care about imap and pop3
+  if (type.EqualsLiteral("imap") || type.EqualsLiteral("pop3")) {
+    // imap and pop3 account should have an Inbox
+    nsCOMPtr<nsIMsgFolder> rootMsgFolder;
+    rv = server->GetRootMsgFolder(getter_AddRefs(rootMsgFolder));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!rootMsgFolder) return NS_ERROR_FAILURE;
+
+    rootMsgFolder->GetFolderWithFlags(nsMsgFolderFlags::Inbox, inboxFolder);
+    if (!*inboxFolder) return NS_ERROR_FAILURE;
+  }
+  return NS_OK;
+}
+
+//*****************************************************************************
+// Encapsulate the XP DB stuff required to enumerate messages
+
+class MsgMapiListContext {
+ public:
+  MsgMapiListContext() {}
+  ~MsgMapiListContext();
+
+  nsresult OpenDatabase(nsIMsgFolder* folder);
+
+  nsMsgKey GetNext();
+  nsresult MarkRead(nsMsgKey key, bool read);
+
+  lpnsMapiMessage GetMessage(nsMsgKey, unsigned long flFlags);
+  bool IsIMAPHost(void);
+  bool DeleteMessage(nsMsgKey key);
+
+ protected:
+  char* ConvertDateToMapiFormat(time_t);
+  char* ConvertBodyToMapiFormat(nsIMsgDBHdr* hdr);
+  void ConvertRecipientsToMapiFormat(
+      const nsCOMArray<msgIAddressObject>& ourRecips,
+      lpnsMapiRecipDesc mapiRecips, int mapiRecipClass);
+
+  nsCOMPtr<nsIMsgFolder> m_folder;
+  nsCOMPtr<nsIMsgDatabase> m_db;
+  nsCOMPtr<nsIMsgEnumerator> m_msgEnumerator;
+};
+
+LONG CMapiImp::InitContext(unsigned long session,
+                           MsgMapiListContext** listContext) {
+  nsMAPIConfiguration* pMapiConfig =
+      nsMAPIConfiguration::GetMAPIConfiguration();
+  if (!pMapiConfig) return MAPI_E_FAILURE;  // get the singleton obj
+  *listContext = (MsgMapiListContext*)pMapiConfig->GetMapiListContext(session);
+  // This is the first message
+  if (!*listContext) {
+    nsCOMPtr<nsIMsgFolder> inboxFolder;
+    nsresult rv = GetDefaultInbox(getter_AddRefs(inboxFolder));
+    if (NS_FAILED(rv)) {
+      NS_ASSERTION(false, "in init context, no inbox");
+      return (MAPI_E_NO_MESSAGES);
+    }
+
+    *listContext = new MsgMapiListContext;
+    if (!*listContext) return MAPI_E_INSUFFICIENT_MEMORY;
+
+    rv = (*listContext)->OpenDatabase(inboxFolder);
+    if (NS_FAILED(rv)) {
+      pMapiConfig->SetMapiListContext(session, NULL);
+      delete *listContext;
+      NS_ASSERTION(false, "in init context, unable to open db");
+      return MAPI_E_NO_MESSAGES;
+    } else
+      pMapiConfig->SetMapiListContext(session, *listContext);
+  }
+  return SUCCESS_SUCCESS;
+}
+
+STDMETHODIMP CMapiImp::FindNext(unsigned long aSession, unsigned long ulUIParam,
+                                LPSTR lpszMessageType, LPSTR lpszSeedMessageID,
+                                unsigned long flFlags, unsigned long ulReserved,
+                                unsigned char lpszMessageID[64])
+
+{
+  //
+  // If this is true, then this is the first call to this FindNext function
+  // and we should start the enumeration operation.
+  //
+
+  *lpszMessageID = '\0';
+  nsMAPIConfiguration* pMapiConfig =
+      nsMAPIConfiguration::GetMAPIConfiguration();
+  if (!pMapiConfig) {
+    NS_ASSERTION(false, "failed to get config in findnext");
+    return MAPI_E_FAILURE;  // get the singleton obj
+  }
+  MsgMapiListContext* listContext;
+  LONG ret = InitContext(aSession, &listContext);
+  if (ret != SUCCESS_SUCCESS) {
+    NS_ASSERTION(false, "init context failed");
+    return ret;
+  }
+  NS_ASSERTION(listContext, "initContext returned null context");
+  if (listContext) {
+    //    NS_ASSERTION(false, "find next init context succeeded");
+    nsMsgKey nextKey = listContext->GetNext();
+    if (nextKey == nsMsgKey_None) {
+      pMapiConfig->SetMapiListContext(aSession, NULL);
+      delete listContext;
+      return (MAPI_E_NO_MESSAGES);
+    }
+
+    //    TRACE("MAPI: ProcessMAPIFindNext() Found message id = %d\n", nextKey);
+
+    sprintf((char*)lpszMessageID, "%d", nextKey);
+  }
+
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("CMapiImp::FindNext returning key %s", (char*)lpszMessageID));
+  return (SUCCESS_SUCCESS);
+}
+
+STDMETHODIMP CMapiImp::ReadMail(unsigned long aSession, unsigned long ulUIParam,
+                                LPSTR lpszMessageID, unsigned long flFlags,
+                                unsigned long ulReserved,
+                                lpnsMapiMessage* lppMessage) {
+  nsresult irv;
+  nsAutoCString keyString((char*)lpszMessageID);
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("CMapiImp::ReadMail asking for key %s", (char*)lpszMessageID));
+  nsMsgKey msgKey = keyString.ToInteger(&irv);
+  if (NS_FAILED(irv)) {
+    NS_ASSERTION(false, "invalid lpszMessageID");
+    return MAPI_E_INVALID_MESSAGE;
+  }
+  MsgMapiListContext* listContext;
+  LONG ret = InitContext(aSession, &listContext);
+  if (ret != SUCCESS_SUCCESS) {
+    NS_ASSERTION(false, "init context failed in ReadMail");
+    return ret;
+  }
+  *lppMessage = listContext->GetMessage(msgKey, flFlags);
+  NS_ASSERTION(*lppMessage, "get message failed");
+
+  return (*lppMessage) ? SUCCESS_SUCCESS : E_FAIL;
+}
+
+STDMETHODIMP CMapiImp::DeleteMail(unsigned long aSession,
+                                  unsigned long ulUIParam, LPSTR lpszMessageID,
+                                  unsigned long flFlags,
+                                  unsigned long ulReserved) {
+  nsresult irv;
+  nsAutoCString keyString((char*)lpszMessageID);
+  nsMsgKey msgKey = keyString.ToInteger(&irv);
+  // XXX Why do we return success on failure?
+  if (NS_FAILED(irv)) return SUCCESS_SUCCESS;
+  MsgMapiListContext* listContext;
+  LONG ret = InitContext(aSession, &listContext);
+  if (ret != SUCCESS_SUCCESS) return ret;
+  return (listContext->DeleteMessage(msgKey)) ? SUCCESS_SUCCESS
+                                              : MAPI_E_INVALID_MESSAGE;
+}
+
+STDMETHODIMP CMapiImp::SaveMail(unsigned long aSession, unsigned long ulUIParam,
+                                lpnsMapiMessage lppMessage,
+                                unsigned long flFlags, unsigned long ulReserved,
+                                LPSTR lpszMessageID) {
+  MsgMapiListContext* listContext;
+  LONG ret = InitContext(aSession, &listContext);
+  if (ret != SUCCESS_SUCCESS) return ret;
+  return S_OK;
+}
+
+STDMETHODIMP CMapiImp::Logoff(unsigned long aSession) {
+  nsMAPIConfiguration* pConfig = nsMAPIConfiguration::GetMAPIConfiguration();
+
+  if (pConfig->UnRegisterSession((uint32_t)aSession)) return S_OK;
+
+  return E_FAIL;
+}
+
+STDMETHODIMP CMapiImp::CleanUp() {
+  nsMapiHook::CleanUp();
+  return S_OK;
+}
+
+#define MAX_NAME_LEN 256
+
+MsgMapiListContext::~MsgMapiListContext() {
+  if (m_db) m_db->Close(false);
+}
+
+nsresult MsgMapiListContext::OpenDatabase(nsIMsgFolder* folder) {
+  nsresult dbErr = NS_ERROR_FAILURE;
+  if (folder) {
+    m_folder = folder;
+    dbErr = folder->GetMsgDatabase(getter_AddRefs(m_db));
+    if (m_db) dbErr = m_db->EnumerateMessages(getter_AddRefs(m_msgEnumerator));
+  }
+  return dbErr;
+}
+
+bool MsgMapiListContext::IsIMAPHost(void) {
+  if (!m_folder) return FALSE;
+  nsCOMPtr<nsIMsgImapMailFolder> imapFolder = do_QueryInterface(m_folder);
+
+  return imapFolder != nullptr;
+}
+
+nsMsgKey MsgMapiListContext::GetNext() {
+  nsMsgKey key = nsMsgKey_None;
+  bool keepTrying = TRUE;
+
+  //  NS_ASSERTION (m_msgEnumerator && m_db, "need enumerator and db");
+  if (m_msgEnumerator && m_db) {
+    do {
+      keepTrying = FALSE;
+      nsCOMPtr<nsIMsgDBHdr> msgHdr;
+      if (NS_SUCCEEDED(m_msgEnumerator->GetNext(getter_AddRefs(msgHdr))) &&
+          msgHdr) {
+        msgHdr->GetMessageKey(&key);
+
+        // Check here for IMAP message...if not, just return...
+        if (!IsIMAPHost()) return key;
+
+        // If this is an IMAP message, we have to make sure we have a valid
+        // body to work with.
+        uint32_t flags = 0;
+
+        (void)msgHdr->GetFlags(&flags);
+        if (flags & nsMsgMessageFlags::Offline) return key;
+
+        // Ok, if we get here, we have an IMAP message without a body!
+        // We need to keep trying by calling the GetNext member recursively...
+        keepTrying = TRUE;
+      }
+    } while (keepTrying);
+  }
+
+  return key;
+}
+
+nsresult MsgMapiListContext::MarkRead(nsMsgKey key, bool read) {
+  nsresult err = NS_ERROR_FAILURE;
+  NS_ASSERTION(m_db, "no db");
+  if (m_db) err = m_db->MarkRead(key, read, nullptr);
+  return err;
+}
+
+lpnsMapiMessage MsgMapiListContext::GetMessage(nsMsgKey key,
+                                               unsigned long flFlags) {
+  lpnsMapiMessage message =
+      (lpnsMapiMessage)CoTaskMemAlloc(sizeof(nsMapiMessage));
+  memset(message, 0, sizeof(nsMapiMessage));
+  if (message) {
+    nsCString subject;
+    nsCString author;
+    nsCOMPtr<nsIMsgDBHdr> msgHdr;
+
+    m_db->GetMsgHdrForKey(key, getter_AddRefs(msgHdr));
+    if (msgHdr) {
+      msgHdr->GetSubject(subject);
+      message->lpszSubject = (char*)CoTaskMemAlloc(subject.Length() + 1);
+      strcpy((char*)message->lpszSubject, subject.get());
+      uint32_t date;
+      (void)msgHdr->GetDateInSeconds(&date);
+      message->lpszDateReceived = ConvertDateToMapiFormat(date);
+
+      // Pull out the flags info
+      // anything to do with MAPI_SENT? Since we're only reading the Inbox, I
+      // guess not
+      uint32_t ourFlags;
+      (void)msgHdr->GetFlags(&ourFlags);
+      if (!(ourFlags & nsMsgMessageFlags::Read))
+        message->flFlags |= MAPI_UNREAD;
+      if (ourFlags & (nsMsgMessageFlags::MDNReportNeeded |
+                      nsMsgMessageFlags::MDNReportSent))
+        message->flFlags |= MAPI_RECEIPT_REQUESTED;
+
+      // Pull out the author/originator info
+      message->lpOriginator =
+          (lpnsMapiRecipDesc)CoTaskMemAlloc(sizeof(nsMapiRecipDesc));
+      memset(message->lpOriginator, 0, sizeof(nsMapiRecipDesc));
+      if (message->lpOriginator) {
+        msgHdr->GetAuthor(getter_Copies(author));
+        ConvertRecipientsToMapiFormat(EncodedHeader(author),
+                                      message->lpOriginator, MAPI_ORIG);
+      }
+      // Pull out the To/CC info
+      nsCString recipients, ccList;
+      msgHdr->GetRecipients(getter_Copies(recipients));
+      msgHdr->GetCcList(getter_Copies(ccList));
+
+      nsCOMArray<msgIAddressObject> parsedToRecips = EncodedHeader(recipients);
+      nsCOMArray<msgIAddressObject> parsedCCRecips = EncodedHeader(ccList);
+      uint32_t numToRecips = parsedToRecips.Length();
+      uint32_t numCCRecips = parsedCCRecips.Length();
+
+      message->lpRecips = (lpnsMapiRecipDesc)CoTaskMemAlloc(
+          (numToRecips + numCCRecips) * sizeof(MapiRecipDesc));
+      memset(message->lpRecips, 0,
+             (numToRecips + numCCRecips) * sizeof(MapiRecipDesc));
+      if (message->lpRecips) {
+        ConvertRecipientsToMapiFormat(parsedToRecips, message->lpRecips,
+                                      MAPI_TO);
+        ConvertRecipientsToMapiFormat(parsedCCRecips,
+                                      &message->lpRecips[numToRecips], MAPI_CC);
+      }
+
+      MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+              ("MsgMapiListContext::GetMessage flags=%lu subject %s date %s "
+               "sender %s",
+               flFlags, (char*)message->lpszSubject,
+               (char*)message->lpszDateReceived, author.get()));
+
+      // Convert any body text that we have locally
+      if (!(flFlags & MAPI_ENVELOPE_ONLY))
+        message->lpszNoteText = (char*)ConvertBodyToMapiFormat(msgHdr);
+    }
+    if (!(flFlags & (MAPI_PEEK | MAPI_ENVELOPE_ONLY)))
+      m_db->MarkRead(key, true, nullptr);
+  }
+  return message;
+}
+
+char* MsgMapiListContext::ConvertDateToMapiFormat(time_t ourTime) {
+  char* date = (char*)CoTaskMemAlloc(32);
+  if (date) {
+    // MAPI time format is YYYY/MM/DD HH:MM
+    // Note that we're not using XP_StrfTime because that localizes the time
+    // format, and the way I read the MAPI spec is that their format is
+    // canonical, not localized.
+    struct tm* local = localtime(&ourTime);
+    if (local)
+      strftime(date, 32, "%Y/%m/%d %I:%M",
+               local);  // use %H if hours should be 24 hour format
+  }
+  return date;
+}
+
+void MsgMapiListContext::ConvertRecipientsToMapiFormat(
+    const nsCOMArray<msgIAddressObject>& recipients,
+    lpnsMapiRecipDesc mapiRecips, int mapiRecipClass) {
+  nsTArray<nsCString> names, addresses;
+  ExtractAllAddresses(recipients, UTF16ArrayAdapter<>(names),
+                      UTF16ArrayAdapter<>(addresses));
+
+  size_t numAddresses = names.Length();
+  for (size_t i = 0; i < numAddresses; i++) {
+    if (!names[i].IsEmpty()) {
+      mapiRecips[i].lpszName = (char*)CoTaskMemAlloc(names[i].Length() + 1);
+      if (mapiRecips[i].lpszName)
+        strcpy((char*)mapiRecips[i].lpszName, names[i].get());
+    }
+    if (!addresses[i].IsEmpty()) {
+      mapiRecips[i].lpszName = (char*)CoTaskMemAlloc(addresses[i].Length() + 1);
+      if (mapiRecips[i].lpszName)
+        strcpy((char*)mapiRecips[i].lpszName, addresses[i].get());
+    }
+    mapiRecips[i].ulRecipClass = mapiRecipClass;
+  }
+}
+
+char* MsgMapiListContext::ConvertBodyToMapiFormat(nsIMsgDBHdr* hdr) {
+  const int kBufLen =
+      64000;  // I guess we only return the first 64K of a message.
+#define EMPTY_MESSAGE_LINE(buf) \
+  (buf[0] == '\r' || buf[0] == '\n' || buf[0] == '\0')
+
+  nsCOMPtr<nsIMsgFolder> folder;
+  hdr->GetFolder(getter_AddRefs(folder));
+  if (!folder) return nullptr;
+
+  nsCOMPtr<nsIFile> localFile;
+  folder->GetFilePath(getter_AddRefs(localFile));
+
+  nsresult rv;
+  nsCOMPtr<nsIFileInputStream> fileStream =
+      do_CreateInstance(NS_LOCALFILEINPUTSTREAM_CONTRACTID, &rv);
+  NS_ENSURE_SUCCESS(rv, nullptr);
+
+  rv = fileStream->Init(localFile, PR_RDONLY, 0664,
+                        false);  // just have to read the messages
+  NS_ENSURE_SUCCESS(rv, nullptr);
+
+  nsCOMPtr<nsILineInputStream> fileLineStream = do_QueryInterface(fileStream);
+  if (!fileLineStream) return nullptr;
+
+  // ### really want to skip past headers...
+  uint64_t messageOffset;
+  uint32_t lineCount;
+  hdr->GetMessageOffset(&messageOffset);
+  hdr->GetLineCount(&lineCount);
+  nsCOMPtr<nsISeekableStream> seekableStream = do_QueryInterface(fileStream);
+  seekableStream->Seek(PR_SEEK_SET, messageOffset);
+  bool hasMore = true;
+  nsAutoCString curLine;
+
+  while (hasMore)  // advance past message headers
+  {
+    nsresult rv = fileLineStream->ReadLine(curLine, &hasMore);
+    if (NS_FAILED(rv) || EMPTY_MESSAGE_LINE(curLine)) break;
+  }
+  uint32_t msgSize;
+  hdr->GetMessageSize(&msgSize);
+  if (msgSize > kBufLen) msgSize = kBufLen - 1;
+  // this is too big, since it includes the msg hdr size...oh well
+  char* body = (char*)CoTaskMemAlloc(msgSize + 1);
+
+  if (!body) return nullptr;
+  int32_t bytesCopied = 0;
+  for (hasMore = TRUE; lineCount > 0 && hasMore && NS_SUCCEEDED(rv);
+       lineCount--) {
+    rv = fileLineStream->ReadLine(curLine, &hasMore);
+    if (NS_FAILED(rv)) break;
+    curLine.Append(CRLF);
+    // make sure we have room left
+    if (bytesCopied + curLine.Length() < msgSize) {
+      strcpy(body + bytesCopied, curLine.get());
+      bytesCopied += curLine.Length();
+    }
+  }
+  MOZ_LOG(MAPI, mozilla::LogLevel::Debug,
+          ("ConvertBodyToMapiFormat size=%x allocated size %x body = %100.100s",
+           bytesCopied, msgSize + 1, (char*)body));
+  body[bytesCopied] = '\0';  // rhp - fix last line garbage...
+  return body;
+}
+
+//*****************************************************************************
+// MSGMAPI API implementation
+
+static void msg_FreeMAPIFile(lpMapiFileDesc f) {
+  if (f) {
+    CoTaskMemFree(f->lpszPathName);
+    CoTaskMemFree(f->lpszFileName);
+  }
+}
+
+static void msg_FreeMAPIRecipient(lpMapiRecipDesc rd) {
+  if (rd) {
+    if (rd->lpszName) CoTaskMemFree(rd->lpszName);
+    if (rd->lpszAddress) CoTaskMemFree(rd->lpszAddress);
+    // CoTaskMemFree(rd->lpEntryID);
+  }
+}
+
+extern "C" void MSG_FreeMapiMessage(lpMapiMessage msg) {
+  ULONG i;
+
+  if (msg) {
+    CoTaskMemFree(msg->lpszSubject);
+    CoTaskMemFree(msg->lpszNoteText);
+    CoTaskMemFree(msg->lpszMessageType);
+    CoTaskMemFree(msg->lpszDateReceived);
+    CoTaskMemFree(msg->lpszConversationID);
+
+    if (msg->lpOriginator) msg_FreeMAPIRecipient(msg->lpOriginator);
+
+    for (i = 0; i < msg->nRecipCount; i++)
+      if (&(msg->lpRecips[i]) != nullptr)
+        msg_FreeMAPIRecipient(&(msg->lpRecips[i]));
+
+    CoTaskMemFree(msg->lpRecips);
+
+    for (i = 0; i < msg->nFileCount; i++)
+      if (&(msg->lpFiles[i]) != nullptr) msg_FreeMAPIFile(&(msg->lpFiles[i]));
+
+    CoTaskMemFree(msg->lpFiles);
+
+    CoTaskMemFree(msg);
+  }
+}
+
+extern "C" bool MsgMarkMapiMessageRead(nsIMsgFolder* folder, nsMsgKey key,
+                                       bool read) {
+  bool success = FALSE;
+  MsgMapiListContext* context = new MsgMapiListContext();
+  if (context) {
+    if (NS_SUCCEEDED(context->OpenDatabase(folder))) {
+      if (NS_SUCCEEDED(context->MarkRead(key, read))) success = TRUE;
+    }
+    delete context;
+  }
+  return success;
+}
+
+bool MsgMapiListContext::DeleteMessage(nsMsgKey key) {
+  if (!m_db) return FALSE;
+
+  if (!IsIMAPHost()) {
+    nsTArray<nsMsgKey> doomed({key});
+    return NS_SUCCEEDED((m_db->DeleteMessages(doomed, nullptr)));
+  }
+#if 0
+  else if ( m_folder->GetIMAPFolderInfoMail() )
+  {
+    AutoTArray<nsMsgKey, 1> messageKeys;
+    messageKeys.AppendElement(key);
+
+    (m_folder->GetIMAPFolderInfoMail())->DeleteSpecifiedMessages(pane, messageKeys, nsMsgKey_None);
+    m_db->DeleteMessage(key, nullptr, FALSE);
+    return TRUE;
+  }
+#endif
+  else {
+    return FALSE;
+  }
+}
+
+/* Return TRUE on success, FALSE on failure */
+extern "C" bool MSG_DeleteMapiMessage(nsIMsgFolder* folder, nsMsgKey key) {
+  bool success = FALSE;
+  MsgMapiListContext* context = new MsgMapiListContext();
+  if (context) {
+    if (NS_SUCCEEDED(context->OpenDatabase(folder))) {
+      success = context->DeleteMessage(key);
+    }
+
+    delete context;
+  }
+
+  return success;
+}
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiImp.h b/comm/mailnews/mapi/mapihook/src/msgMapiImp.h
new file mode 100644
index 0000000000..b83f0566a0
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiImp.h
@@ -0,0 +1,79 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MSG_MAPI_IMP_H
+#define MSG_MAPI_IMP_H
+
+#include "msgMapi.h"
+#include "nspr.h"
+#include "nscore.h"
+#include "nsISupportsImpl.h"  // ThreadSafeAutoRefCnt
+
+class nsIMsgFolder;
+class MsgMapiListContext;
+
+const CLSID CLSID_CMapiImp = {0x29f458be,
+                              0x8866,
+                              0x11d5,
+                              {0xa3, 0xdd, 0x0, 0xb0, 0xd0, 0xf3, 0xba, 0xa7}};
+
+// this class implements the MS COM interface nsIMapi that provides the methods
+// called by mapi32.dll to perform the mail operations as specified by MAPI.
+// These class methods in turn use the Mozilla Mail XPCOM interfaces to do so.
+class CMapiImp : public nsIMapi {
+ public:
+  // IUnknown
+
+  STDMETHODIMP QueryInterface(const IID& aIid, void** aPpv);
+  STDMETHODIMP_(ULONG) AddRef();
+  STDMETHODIMP_(ULONG) Release();
+
+  // Interface INsMapi
+
+  STDMETHODIMP Login(unsigned long aUIArg, LPSTR aLogin, LPSTR aPassWord,
+                     unsigned long aFlags, unsigned long* aSessionId);
+
+  STDMETHODIMP SendMail(unsigned long aSession, lpnsMapiMessage aMessage,
+                        unsigned long aFlags, unsigned long aReserved);
+
+  STDMETHODIMP SendDocuments(unsigned long aSession, LPSTR aDelimChar,
+                             LPSTR aFilePaths, LPSTR aFileNames, ULONG aFlags);
+
+  STDMETHODIMP FindNext(unsigned long aSession, unsigned long ulUIParam,
+                        LPSTR lpszMessageType, LPSTR lpszSeedMessageID,
+                        unsigned long flFlags, unsigned long ulReserved,
+                        unsigned char lpszMessageID[64]);
+
+  STDMETHODIMP ReadMail(unsigned long lhSession, unsigned long ulUIParam,
+                        LPSTR lpszMessageID, unsigned long flFlags,
+                        unsigned long ulReserved, lpnsMapiMessage* lppMessage);
+  STDMETHODIMP DeleteMail(unsigned long lhSession, unsigned long ulUIParam,
+                          LPSTR lpszMessageID, unsigned long flFlags,
+                          unsigned long ulReserved);
+  STDMETHODIMP SaveMail(unsigned long lhSession, unsigned long ulUIParam,
+                        lpnsMapiMessage lppMessage, unsigned long flFlags,
+                        unsigned long ulReserved, LPSTR lpszMessageID);
+
+  STDMETHODIMP Initialize();
+  STDMETHODIMP IsValid();
+  STDMETHODIMP IsValidSession(unsigned long aSession);
+
+  STDMETHODIMP SendMailW(unsigned long aSession, lpnsMapiMessageW aMessage,
+                         unsigned long aFlags, unsigned long aReserved);
+
+  STDMETHODIMP Logoff(unsigned long aSession);
+  STDMETHODIMP CleanUp();
+
+  CMapiImp();
+  virtual ~CMapiImp();
+
+  LONG InitContext(unsigned long session, MsgMapiListContext** listContext);
+  nsresult GetDefaultInbox(nsIMsgFolder** inboxFolder);
+
+ private:
+  PRLock* m_Lock;
+  mozilla::ThreadSafeAutoRefCnt m_cRef;
+};
+
+#endif  // MSG_MAPI_IMP_H
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiMain.cpp b/comm/mailnews/mapi/mapihook/src/msgMapiMain.cpp
new file mode 100644
index 0000000000..0e8d4cacac
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiMain.cpp
@@ -0,0 +1,248 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <mapidefs.h>
+#include <mapi.h>
+
+#include "msgCore.h"
+#include "nsComposeStrings.h"
+#include "msgMapiMain.h"
+#include "nsCOMPtr.h"
+
+nsMAPIConfiguration* nsMAPIConfiguration::m_pSelfRef = nullptr;
+uint32_t nsMAPIConfiguration::session_generator = 0;
+uint32_t nsMAPIConfiguration::sessionCount = 0;
+
+nsMAPIConfiguration* nsMAPIConfiguration::GetMAPIConfiguration() {
+  if (m_pSelfRef == nullptr) m_pSelfRef = new nsMAPIConfiguration();
+
+  return m_pSelfRef;
+}
+
+nsMAPIConfiguration::nsMAPIConfiguration() : m_nMaxSessions(MAX_SESSIONS) {
+  m_Lock = PR_NewLock();
+}
+
+nsMAPIConfiguration::~nsMAPIConfiguration() {
+  if (m_Lock) PR_DestroyLock(m_Lock);
+}
+
+void nsMAPIConfiguration::OpenConfiguration() {
+  // No. of max. sessions is set to MAX_SESSIONS.  In future
+  // if it is decided to have configuration (registry)
+  // parameter, this function can be used to set the
+  // max sessions;
+
+  return;
+}
+
+int16_t nsMAPIConfiguration::RegisterSession(
+    uint32_t aHwnd, const nsCString& aUserName, const nsCString& aPassword,
+    bool aForceDownLoad, bool aNewSession, uint32_t* aSession,
+    const char* aIdKey) {
+  int16_t nResult = 0;
+  uint32_t n_SessionId = 0;
+
+  PR_Lock(m_Lock);
+
+  // Check whether max sessions is exceeded
+
+  if (sessionCount >= m_nMaxSessions) {
+    PR_Unlock(m_Lock);
+    return -1;
+  }
+
+  if (!aUserName.IsEmpty()) n_SessionId = m_ProfileMap.Get(aUserName);
+
+  // try to share a session; if not create a session
+  if (n_SessionId > 0) {
+    nsMAPISession* pTemp = nullptr;
+    m_SessionMap.Get(n_SessionId, &pTemp);
+    if (pTemp != nullptr) {
+      pTemp->IncrementSession();
+      *aSession = n_SessionId;
+      nResult = 1;
+    }
+  } else if (aNewSession ||
+             n_SessionId == 0)  // checking for n_SessionId is a concession
+  {
+    // create a new session; if new session is specified OR there is no session
+    session_generator++;
+
+    // I don't think there will be (2 power 32) sessions alive
+    // in a cycle. This is an assumption.
+    if (session_generator == 0) session_generator++;
+    m_SessionMap.InsertOrUpdate(
+        session_generator,
+        mozilla::MakeUnique<nsMAPISession>(aHwnd, aUserName, aPassword,
+                                           aForceDownLoad, aIdKey));
+    if (!aUserName.IsEmpty())
+      m_ProfileMap.InsertOrUpdate(aUserName, session_generator);
+    *aSession = session_generator;
+    sessionCount++;
+    nResult = 1;
+  }
+
+  PR_Unlock(m_Lock);
+  return nResult;
+}
+
+bool nsMAPIConfiguration::UnRegisterSession(uint32_t aSessionID) {
+  bool bResult = false;
+
+  PR_Lock(m_Lock);
+
+  if (aSessionID != 0) {
+    nsMAPISession* pTemp = nullptr;
+    m_SessionMap.Get(aSessionID, &pTemp);
+
+    if (pTemp != nullptr) {
+      if (pTemp->DecrementSession() == 0) {
+        if (pTemp->m_pProfileName.get() != nullptr)
+          m_ProfileMap.Remove(pTemp->m_pProfileName);
+        m_SessionMap.Remove(aSessionID);
+        sessionCount--;
+        bResult = true;
+      }
+    }
+  }
+
+  PR_Unlock(m_Lock);
+  return bResult;
+}
+
+bool nsMAPIConfiguration::IsSessionValid(uint32_t aSessionID) {
+  if (aSessionID == 0) return false;
+  bool retValue = false;
+  PR_Lock(m_Lock);
+  retValue = m_SessionMap.Get(aSessionID, NULL);
+  PR_Unlock(m_Lock);
+  return retValue;
+}
+
+char16_t* nsMAPIConfiguration::GetPassword(uint32_t aSessionID) {
+  char16_t* pResult = nullptr;
+
+  PR_Lock(m_Lock);
+
+  if (aSessionID != 0) {
+    nsMAPISession* pTemp = nullptr;
+    m_SessionMap.Get(aSessionID, &pTemp);
+
+    if (pTemp) pResult = pTemp->GetPassword();
+  }
+  PR_Unlock(m_Lock);
+  return pResult;
+}
+
+void* nsMAPIConfiguration::GetMapiListContext(uint32_t aSessionID) {
+  void* pResult = nullptr;
+
+  PR_Lock(m_Lock);
+
+  if (aSessionID != 0) {
+    nsMAPISession* pTemp = nullptr;
+    m_SessionMap.Get(aSessionID, &pTemp);
+    if (pTemp) pResult = pTemp->GetMapiListContext();
+  }
+
+  PR_Unlock(m_Lock);
+  return pResult;
+}
+
+void nsMAPIConfiguration::SetMapiListContext(uint32_t aSessionID,
+                                             void* mapiListContext) {
+  PR_Lock(m_Lock);
+
+  if (aSessionID != 0) {
+    nsMAPISession* pTemp = nullptr;
+    m_SessionMap.Get(aSessionID, &pTemp);
+    if (pTemp) pTemp->SetMapiListContext(mapiListContext);
+  }
+
+  PR_Unlock(m_Lock);
+}
+
+void nsMAPIConfiguration::GetIdKey(uint32_t aSessionID, nsCString& aKey) {
+  PR_Lock(m_Lock);
+  if (aSessionID != 0) {
+    nsMAPISession* pTemp = nullptr;
+    m_SessionMap.Get(aSessionID, &pTemp);
+    if (pTemp) pTemp->GetIdKey(aKey);
+  }
+  PR_Unlock(m_Lock);
+  return;
+}
+
+// util func
+HRESULT nsMAPIConfiguration::GetMAPIErrorFromNSError(nsresult res) {
+  HRESULT hr = SUCCESS_SUCCESS;
+
+  if (NS_SUCCEEDED(res)) return hr;
+
+  // if failure return the related MAPI failure code
+  switch (res) {
+    case NS_MSG_NO_RECIPIENTS:
+      hr = MAPI_E_BAD_RECIPTYPE;
+      break;
+    case NS_ERROR_COULD_NOT_GET_USERS_MAIL_ADDRESS:
+    case NS_ERROR_COULD_NOT_GET_SENDERS_IDENTITY:
+      // Something went wrong with the sender. There's no error we can map to
+      // so we use a general error, see:
+      // https://msdn.microsoft.com/en-us/library/hh802867(v=vs.85).aspx
+      hr = MAPI_E_FAILURE;
+      break;
+    case NS_ERROR_SMTP_AUTH_FAILURE:
+    case NS_ERROR_SMTP_AUTH_GSSAPI:
+    case NS_ERROR_SMTP_AUTH_MECH_NOT_SUPPORTED:
+    case NS_ERROR_SMTP_AUTH_CHANGE_ENCRYPT_TO_PLAIN_NO_SSL:
+    case NS_ERROR_SMTP_AUTH_CHANGE_ENCRYPT_TO_PLAIN_SSL:
+    case NS_ERROR_SMTP_AUTH_CHANGE_PLAIN_TO_ENCRYPT:
+      hr = MAPI_E_LOGIN_FAILURE;
+      break;
+    case NS_MSG_UNABLE_TO_OPEN_FILE:
+    case NS_MSG_UNABLE_TO_OPEN_TMP_FILE:
+    case NS_MSG_COULDNT_OPEN_FCC_FOLDER:
+    case NS_ERROR_FILE_INVALID_PATH:
+      hr = MAPI_E_ATTACHMENT_OPEN_FAILURE;
+      break;
+    case NS_ERROR_FILE_NOT_FOUND:
+      hr = MAPI_E_ATTACHMENT_NOT_FOUND;
+      break;
+    case NS_MSG_ERROR_WRITING_FILE:
+    case NS_MSG_UNABLE_TO_SAVE_TEMPLATE:
+    case NS_MSG_UNABLE_TO_SAVE_DRAFT:
+      hr = MAPI_E_ATTACHMENT_WRITE_FAILURE;
+      break;
+    default:
+      hr = MAPI_E_FAILURE;
+      break;
+  }
+
+  return hr;
+}
+
+nsMAPISession::nsMAPISession(uint32_t aHwnd, const nsCString& aUserName,
+                             const nsCString& aPassword, bool aForceDownLoad,
+                             const char* aKey)
+    : m_nShared(1), m_pIdKey(aKey) {
+  m_listContext = NULL;
+  m_pProfileName = aUserName;
+  m_pPassword = aPassword;
+}
+
+nsMAPISession::~nsMAPISession() {}
+
+uint32_t nsMAPISession::IncrementSession() { return ++m_nShared; }
+
+uint32_t nsMAPISession::DecrementSession() { return --m_nShared; }
+
+uint32_t nsMAPISession::GetSessionCount() { return m_nShared; }
+
+char16_t* nsMAPISession::GetPassword() { return (char16_t*)m_pPassword.get(); }
+
+void nsMAPISession::GetIdKey(nsCString& aKey) {
+  aKey = m_pIdKey;
+  return;
+}
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiMain.h b/comm/mailnews/mapi/mapihook/src/msgMapiMain.h
new file mode 100644
index 0000000000..fcca6ca541
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiMain.h
@@ -0,0 +1,80 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MSG_MAPI_MAIN_H_
+#define MSG_MAPI_MAIN_H_
+
+#define MAX_NAME_LEN 256
+#define MAX_PW_LEN 256
+#define MAX_SESSIONS 50
+#define MAPI_SENDCOMPLETE_EVENT "SendCompletionEvent"
+
+#define MAPI_PROPERTIES_CHROME "chrome://messenger-mapi/locale/mapi.properties"
+#define PREF_MAPI_WARN_PRIOR_TO_BLIND_SEND "mapi.blind-send.warn"
+#define PREF_MAPI_BLIND_SEND_ENABLED "mapi.blind-send.enabled"
+
+#include "nspr.h"
+#include "nsTHashMap.h"
+#include "nsClassHashtable.h"
+#include "nsString.h"
+
+class nsMAPISession;
+
+class nsMAPIConfiguration {
+ private:
+  static uint32_t session_generator;
+  static uint32_t sessionCount;
+  static nsMAPIConfiguration* m_pSelfRef;
+  PRLock* m_Lock;
+  uint32_t m_nMaxSessions;
+
+  nsTHashMap<nsCStringHashKey, uint32_t> m_ProfileMap;
+  nsClassHashtable<nsUint32HashKey, nsMAPISession> m_SessionMap;
+  nsMAPIConfiguration();
+  ~nsMAPIConfiguration();
+
+ public:
+  static nsMAPIConfiguration* GetMAPIConfiguration();
+  void OpenConfiguration();
+  int16_t RegisterSession(uint32_t aHwnd, const nsCString& aUserName,
+                          const nsCString& aPassword, bool aForceDownLoad,
+                          bool aNewSession, uint32_t* aSession,
+                          const char* aIdKey);
+  bool IsSessionValid(uint32_t aSessionID);
+  bool UnRegisterSession(uint32_t aSessionID);
+  char16_t* GetPassword(uint32_t aSessionID);
+  void GetIdKey(uint32_t aSessionID, nsCString& aKey);
+  void* GetMapiListContext(uint32_t aSessionID);
+  void SetMapiListContext(uint32_t aSessionID, void* mapiListContext);
+
+  // a util func
+  static HRESULT GetMAPIErrorFromNSError(nsresult res);
+};
+
+class nsMAPISession {
+  friend class nsMAPIConfiguration;
+
+ private:
+  uint32_t m_nShared;
+  nsCString m_pIdKey;
+  nsCString m_pProfileName;
+  nsCString m_pPassword;
+  void* m_listContext;  // used by findNext
+
+ public:
+  nsMAPISession(uint32_t aHwnd, const nsCString& aUserName,
+                const nsCString& aPassword, bool aForceDownLoad,
+                const char* aKey);
+  uint32_t IncrementSession();
+  uint32_t DecrementSession();
+  uint32_t GetSessionCount();
+  char16_t* GetPassword();
+  void GetIdKey(nsCString& aKey);
+  ~nsMAPISession();
+  // For enumerating Messages...
+  void SetMapiListContext(void* listContext) { m_listContext = listContext; }
+  void* GetMapiListContext() { return m_listContext; }
+};
+
+#endif  // MSG_MAPI_MAIN_H_
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiSupport.cpp b/comm/mailnews/mapi/mapihook/src/msgMapiSupport.cpp
new file mode 100644
index 0000000000..9fd1655526
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiSupport.cpp
@@ -0,0 +1,101 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#include "nsCOMPtr.h"
+#include "objbase.h"
+#include "nsISupports.h"
+
+#include "mozilla/ModuleUtils.h"
+#include "mozilla/Services.h"
+#include "nsIObserverService.h"
+#include "Registry.h"
+#include "msgMapiSupport.h"
+
+#include "msgMapiImp.h"
+
+/** Implementation of the nsIMapiSupport interface.
+ *  Use standard implementation of nsISupports stuff.
+ */
+
+NS_IMPL_ISUPPORTS(nsMapiSupport, nsIMapiSupport, nsIObserver)
+
+NS_IMETHODIMP
+nsMapiSupport::Observe(nsISupports* aSubject, const char* aTopic,
+                       const char16_t* aData) {
+  nsresult rv = NS_OK;
+
+  if (!strcmp(aTopic, "profile-after-change")) return InitializeMAPISupport();
+
+  if (!strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID))
+    return ShutdownMAPISupport();
+
+  nsCOMPtr<nsIObserverService> observerService =
+      mozilla::services::GetObserverService();
+  NS_ENSURE_TRUE(observerService, NS_ERROR_UNEXPECTED);
+
+  rv = observerService->AddObserver(this, "profile-after-change", false);
+  if (NS_FAILED(rv)) return rv;
+
+  rv = observerService->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
+  if (NS_FAILED(rv)) return rv;
+
+  return rv;
+}
+
+nsMapiSupport::nsMapiSupport() : m_dwRegister(0), m_nsMapiFactory(nullptr) {}
+
+nsMapiSupport::~nsMapiSupport() {}
+
+NS_IMETHODIMP
+nsMapiSupport::InitializeMAPISupport() {
+  ::OleInitialize(nullptr);
+
+  if (m_nsMapiFactory ==
+      nullptr)  // No Registering if already done.  Sanity Check!!
+  {
+    m_nsMapiFactory = new CMapiFactory();
+
+    if (m_nsMapiFactory != nullptr) {
+      HRESULT hr = ::CoRegisterClassObject(CLSID_CMapiImp, m_nsMapiFactory,
+                                           CLSCTX_LOCAL_SERVER,
+                                           REGCLS_MULTIPLEUSE, &m_dwRegister);
+
+      if (FAILED(hr)) {
+        m_nsMapiFactory->Release();
+        m_nsMapiFactory = nullptr;
+        return NS_ERROR_FAILURE;
+      }
+    }
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMapiSupport::ShutdownMAPISupport() {
+  if (m_dwRegister != 0) ::CoRevokeClassObject(m_dwRegister);
+
+  if (m_nsMapiFactory != nullptr) {
+    m_nsMapiFactory->Release();
+    m_nsMapiFactory = nullptr;
+  }
+
+  ::OleUninitialize();
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMapiSupport::RegisterServer() {
+  // TODO: Figure out what kind of error propagation to pass back
+  ::RegisterServer(CLSID_CMapiImp, L"Mozilla MAPI", L"MozillaMapi",
+                   L"MozillaMapi.1");
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMapiSupport::UnRegisterServer() {
+  // TODO: Figure out what kind of error propagation to pass back
+  ::UnregisterServer(CLSID_CMapiImp, L"MozillaMapi", L"MozillaMapi.1");
+  return NS_OK;
+}
diff --git a/comm/mailnews/mapi/mapihook/src/msgMapiSupport.h b/comm/mailnews/mapi/mapihook/src/msgMapiSupport.h
new file mode 100644
index 0000000000..af17ea637c
--- /dev/null
+++ b/comm/mailnews/mapi/mapihook/src/msgMapiSupport.h
@@ -0,0 +1,35 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MSG_MAPI_SUPPORT_H_
+#define MSG_MAPI_SUPPORT_H_
+
+#include "nsIObserver.h"
+#include "nsIMapiSupport.h"
+#include "msgMapiFactory.h"
+
+#define NS_IMAPISUPPORT_CID                          \
+  {                                                  \
+    0x8967fed2, 0xc8bb, 0x11d5, {                    \
+      0xa3, 0xe9, 0x00, 0xb0, 0xd0, 0xf3, 0xba, 0xa7 \
+    }                                                \
+  }
+
+class nsMapiSupport : public nsIMapiSupport, public nsIObserver {
+ public:
+  nsMapiSupport();
+
+  // Declare all interface methods we must implement.
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+  NS_DECL_NSIMAPISUPPORT
+
+ private:
+  virtual ~nsMapiSupport();
+
+  DWORD m_dwRegister;
+  CMapiFactory* m_nsMapiFactory;
+};
+
+#endif  // MSG_MAPI_SUPPORT_H_