In the most recent cumulative update of Windows 10 at the time of writing - "Fall Creators Update", version 1709 - Microsoft has finally done what the fans of good old Outlook Express and its subsequent reincarnation Windows Mail were so afraid of: they uprooted it from the file system and Windows registry. Up to version 1703 inclusive, the method described here worked well, but now it is impossible to enable the inactive mail client this way - because of its absence in the OS. But another Microsoft's attempt to prove more stubborn than geeks ended up just like the previous ones: a way to implement the mailer back into the system was found.

Enthusiasts returned the program almost full functionality in version 1709. Almost - since it is not yet possible to restore MAPI clients in working order. But, hopefully, this problem will be solved soon.

I tested the results of research and, it seems to me, found the necessary minimum of changes to the files and the registry, which is sufficient to restore all the functions of WinMail (excluding MAPI). Let me share the final result.

Disclaimer: the technique is new, so it is strongly recommended to try it out first on the testing environment rather than on the main system. And, of course, start by creating backup copies of personal settings: mail storage, accounts, user settings.

Now we can get to the point.

Download one of zip-archives in correspondence with the bit depth of your operating system.

32-bit OS:

EnableWinMailWin10_1709_x86_en.zip
2018-01-02   Windows  2.49 MB  722	Download

64-bit OS:

EnableWinMailWin10_1709_x64_en.zip
2018-01-02   Windows  2.72 MB  2456	Download

The sequence of actions for both bit capacities is the same:

1. After upgrading to version 1709, only 4 address book files and empty subfolders of interface languages remain in the mailer folder %ProgramFiles%\Windows Mail. Recover WinMail files by copying the contents of the Windows Mail folder from the downloaded archive to the mailer folder.

   If you use Windows localization different from English, you will have to restore the appropriate localization files from working copy of WinMail on Vista. For English, the en-US folder is enough.

2. Copy files from the system32 folder in the archive to the folder of the same name in the system directory - %SystemRoot%\system32.

3. Run the WinMailEdit.reg file. This adds certain functionality to the registry, as it was described in Retrospective review. But now a small but crucial chunk has been added to the file code:

   ; WinMail Class Register -------------------------------------------------------
   [HKEY_CLASSES_ROOT\CLSID\{39AE2AEA-D4D5-4DA0-AE47-C020E1BE4BE5}]
   @="CLSID_JetDatabaseSession"
    
   [HKEY_CLASSES_ROOT\CLSID\{39AE2AEA-D4D5-4DA0-AE47-C020E1BE4BE5}\InprocServer32]
   @=hex(2):25,00,50,00,72,00,6f,00,67,00,72,00,61,00,6d,00,46,00,69,00,6c,00,65,\
     00,73,00,25,00,5c,00,57,00,69,00,6e,00,64,00,6f,00,77,00,73,00,20,00,4d,00,\
     61,00,69,00,6c,00,5c,00,6d,00,73,00,6f,00,65,00,2e,00,64,00,6c,00,6c,00,00,\
     00
   "ThreadingModel"="Both"
    
   ; WinMail Cur User -------------------------------------------------------------
   [HKEY_CURRENT_USER\Software\Microsoft\Windows Mail Setup]
   "DelayStartTime"=hex:fa,71,45,36,d1,cd,cf,01
   "DelayInitialized"=dword:00000004
    

   This script restores the WinMail class registration and initializes a few settings of current user. Without the first thing, the program simply does not run; without the second - it will start, but prior to that it will detect the "broken storage" and supposedly fix it. Both together will make the application start smoothly.

Now Windows Mail should launch steadily and work correctly.

UPD: WinMail + MAPI: See next article.