I wrote a FileSystem Filter driver. I call the IoVolumeDeviceToDosName( ) in
Win2K3 driver, and I get the error that the device is not supported.
I use the exact same parameters in Win2K when I call
RtlVolumeDeviceToDosName( ), and it works like a charm...What am I missing?

Win2K works.
status = RtlVolumeDeviceToDosName( irpSp->DeviceObject,
&DosName );

Win2K3 doesn't work.
status = IoVolumeDeviceToDosName( irpSp->DeviceObject,
&DosName );
Regards,
-SteveC