Windows

Point value changed by question poster.

Have you confirmed that this application is designed to run in a TS environment? Can you run it in a standard Windows environment? It sounds to me like the application is trying to do something "illegal" (read - not allowed by the Win2K3 kernel) on the 16-bit side, like possibly some sort of direct control of a hardware resource, which is then causing the NTVDM to error out. I would consult with the programmers or, if it's a 3rd party app, with the company you purchased it from, to see if they can determine the cause.

Hope this helps!

In this case, the app. was running OK, but the developer/implementer decided that Remote Desktop Web Connection was required for some users to access it. Remote Desktop Web Connection (part of WWW Service/IIS) was added to the system, then SP1 was re-applied to the server.

Since this, we are encountering the NTVDM hard error message whenever we try to do any 16bit work.

I have checked the autoexec.nt and config.nt files, have re-expanded the command.com and ntvdm.exe files, have tested it from admin and user and we get this error all the time now, even trying to just run command.com. I have read all the posts I could find here and looked for this error in KB's with no positive results. Have also reset the env var for TEMP and TMP to C:\TEMP to remove that possible failing.

Are there any requirements to re-install the MS patches after re-installing a SP? Are there files that are replaced that could cause this behaviour if the security patches MS issues after a SP is released replace critical files? How can I safely re-run all the necessary patches if I need to do so?

The matter has been resolved. The problem was caused by an entry in the registry at:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\VirtualDeviceDrivers\VDD

which had an incorrect value in it pointing to a non-existant dll removed when we uninstalled Symantec Corporate Anti-Virus. This somehow caused the NTVDM to fail without an error message highlighting the fact that the file could not be found when the system tried to run it for the VDD value.

Thanks people.

Michael