Hello, I am the computer admin for a library system and we recently purchased 8 new computers for our lab. They all have Windows 7, but for some reason when I try to name several of them or add user accounts for the network I get either the "RPC server is unavailable" error or "The user could not be added because the following error has occurred: The trust relationship between this computer and the primary domain has failed." Only the computers that have the RPC error first are getting the second error (and I have tried rebooting and renaming several times in between -- no luck). Any suggestions?RoseB

Hi, Based on my research, I found the issue can occur if the computer's machine account has the incorrect role or its password has become mismatched with that of the domain database. To resolve the issue, please refer to the following article: Trust Relationship Between Workstation and Domain Fails Thanks, Novak