Lonkero,
From nra's first post:
quote:
The clients aren't member of a central domain (they run a Terminal Server client through the VPN tunnel) so I don't have administrative privs on the machine (is it then at all possible to retrive the info from the registry?)
So the script is not running on the client, it is running on the terminal server. There is no local context to run the script in.

nra, is there nothing else useful in the TS DLL which might provide the information?

Do you map client drives in the same way as you do with Citrix? If so you may be able to check for file versions on the client to determine it's type.