Thanks. I will have a look tomorrow at the GetAdUserGroups to see if that will work for me! Or whenever I have energy to back to that.

I don't believe it is the Winnt issue - although I would prefer to use LDAP. I updated the code to use LDAP and it made zero difference. In point of fact, Howard's udf actually does get the security groups the user is a member of, so the script actually is working just stopping with an error.

I appreciate the age of the script does make it possible that the issue is changes over time. However, I think the post that I linked to and Lonkero's explanation would suggest as wider issue than any specific script.

I will update when I come back to this.