i can search the active directory to find the groups and i can search users
and find out of what groups he's a member.

But now i have to find a group, and find out what groups he's a member of,
but i don't know where to start....

anybody who has an idea?

thxs in advance

IIRC a user account object in Active Directory has a 'Member Of' attribute.
Try a query against that.

How to Share Class Properties Across Processes
no indexof-function for collection object available.
Open a CSV file
What is .NET Redistributable?
How do I shell the following command line or process.start it (very different command!)
Oledb????
Destructor for VB.NET class
With different credentials.
API declarations with fixed length string
CreationTime and Windows File CreationTime why different?