I have a SQL Instance that was previously on an old domain within my company and was moved to a new domain prior to my time as DBA. After the move, none of the logins / AD Groups from the old domain were removed. I recently started removing the old domain logins and since then users are unable to connect. The users are part of the new domain and are members of an AD Group that has appropriate permissions.
I'm at a loss as to why the users can't connect and my next move is to nuke the existing AD Group and rebuild it to try again, but I'd rather not do that just on the off chance that's the problem.
As always, any help is greatly appreciated.