Installation on W2K3 (.NET Enterprise server)

Hi all !
I have a simple install program that installs a SCSI Miniport.
This program uses the SetupDiXXX functions.
It works properly on Win2K and XP.
However it fails on W2K3 Enterprise server.

Has anyone faces similar problems ?

When I take a closer look,
I observe that the function UpdateDriverForPlugAndPlayDevices fails
and returns NO_ERROR. I have correctly specified the INSTALLFLAG_FORCE
as per the documentation.

Any ideas would be appreciated.