When using XPSI and serial tunneling on Windows 2003 Server, this error occurs: NTVDM encountered a hard error


When using XPSI and serial tunneling on Windows 2003 Server, this error occurs:  "NTVDM encountered a hard error"

Product Line

TAC I/A Series


  • XPSI
  • Windows 2003 Server


Environment settings for TEMP and TMP is not 8.3 namespace compatible.


"Most ntvdm errors can be fixed by modifying the TEMP and TMP environment settings to make them 8.3 namespace compatible.
The default path for the TEMP directories is:  %USERPROFILE%\Local Settings\Temp
This will (typically) expand to something like: C:\Documents and Settings\Administrator\Local Settings\Temp

16-bit applications cannot  manage the spaces or long file names, and will generate ntvdm errors, even if not explicitly referencing the TEMP directory.

Either use a common temp location (i.e C:\Temp) or use the short version of the path.  For the Administrator ID, the short filename path is C:\DOCUME~1\ADMINI~1\LOCALS~1\TEMP

Check these names by using ‘dir /x’ The variable settings can then be changed for each user by going into My Computer -> Properties -> Advanced -> Environment Variables -> Set TEMP and TMP to c:\temp or the short filename version

Also, consider the PATH environment variable, and any INI files that may be used. The short filename for the "c:\Program Files" directory is "c:\progra~1"

Here is how to disable 8.3 naming in the registry.
Note - "Edit the registry by using Registry Editor (Regedit.exe or Regedt32.exe). If Registry Editor is used incorrectly, serious problems can occur requiring a reinstallation of the operating system. Use Registry Editor at your own risk."