The VirtualDeviceDriver subkey contains a list of Win32 DLLs that serve as virtual device drivers (VDD). Each VDD entry results in loading that VDD when a virtual MS-DOS machine (VDM) is being created for running an application created for MS-DOS or 16-bit versions of Microsoft Windows. This is the Registry path:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\VirtualDeviceDrivers
VDD REG_MULTI_SZ Filenames
Specifies valid Win32 DLLs that are virtual device drivers.
Default: None—the Windows NT VDDs are built into the system.