You get a DOS Virtual Device Driver failure after you install a program which generates one of the following error messages. If you ignore the message, the program may or may not run. The problem is caused by the program corrupting the VDD value.

16 bit MS-DOS Subsystem
drive:\program path
XXXX. An installable Virtual Device Driver failed DLL initialization. Choose 'Close' to terminate the application.

-or-

16 bit MS-DOS Subsystem
drive:\program path
SYSTEM\CurrentControlSet\Control\VirtualDeviceDrivers. VDD. Virtual Device Driver format in the registry is invalid. Choose 'Close' to terminate the application.

You can resolve the problem by deleting the value, followed by readding the value.

Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Control\VirtualDeviceDrivers
Name: VDD
Type: REG_MULTI_SZ

Delete the value. When you re-add VDD, when the multi-string editor appears with a blank entry. Leave the entry blank and click OK This should resolve the problem. The problem shows up on Windows 2000 and Windows XP systems. It can occur in Windows NT if someone (or some program) deletes the VDD value.

Keywords: Windows 2000 Registry Tip, Windows XP, run, vdd, dll, initialization, error, virtual device driver, installation, program, 16-bit, ms-dos, subsystem