Anyway, I'm stumped based upon snippet you provided. My tests of same structure, when executed from the command line, return proper reply based upon group memberships.

Command line test was simple messagebox display - IF INGROUP (A) <> 0, etc., and proper messagebox displayed every time.

Also added a test group 'R&D' in my domain, edited login script for drive mapping, and login script executed properly. I thought the '&' in group name might be an issue, but does work properly for me so apparently not.

Perhaps the issue is code prior to execution of this section, and the error not surfacing until this section? Don't know, just fishing now.

Bill