It is another runtime problem, but he only people who need that file are those who host at GameRanger and want to create and save new multiplayer missions.
This is a copy of a post on the first page of this thread which has the link to a different runtime files installer:
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Some time ago I received a PM from Shogun about the Mission Editor generating this error message when he tried to run it:

Run-time error 713 Class not registered. MSSTDFMT.DLL

I hit this problem a few weeks ago when I was away in Lyon and I tried to run the Mission Editor on my new laptop.
When I got back I made a VisualBasic installer program for the mission editor, which correctly installs the " MSSTDFMT.DLL" file during the installation process.

"MissionEdPackage.exe" is available here:

Mission Editor Runtimes

If you get that error then download it, and run it on your desktop.
This will create a folder named "MedPackage" and in this folder there is a "Setup.exe" file.


Run the "Setup.exe", let it install the mission editor anywhere (as the reason for running it is to install the missing file), but do not let it overwrite newer versions of files with older ones.

Re-boot and the Mission Editor should now work.

Jel