We joined a new computer to our domain last year with this format (first initial)(lastname)09. The user called after a time, and told us that he was unable to log in. We checked the account and it appeared fine, however no matter what we did we could not get his computer re-joined to the domain. We joined his computer to a workgroup renamed it, and then re-joined it to the domain again with the new name. That worked for a while, but then the user called again and said he was experiencing the same issue again. And again we had to un-join rename then re-join it to the domain. What could be causing this to happen? Could this be a hardware issue with the network card going bad? It seems to work for a few months and then the account just goes bad, and we have to go through the process all over again. I have never seen this except in the case where a card goes bad and is replaced.