Thanks both of you for your replies.

The problem is that the client connects to a central server through the VPN tunnel using a Termibal Server client, therefore the logonscript is executed on the server - and I can't query the OS directly. Les sent me the WTSManager.dll but I haven't had time to test it yet, though I've testet a commandline utility TSQuery from Clusteresis.com that I think used the same procedure calls - and it can't return the OS of the client [Frown]

I guess the only way is port-probing like you suggest. Can KiXtart be used to check for existance of a port?

Thanks!

/Nicolaj