I have a Dell Optiplex 740 running Windows Vista Business. The workstation was on the domain and operating fine for over a year. The other day, the workstation was in a frozen state. I was able to start it up and log in without the network cable attached. I then removed it from the domain and placed it in a workgroup. It operates fine on the network this way. when I try to place it back on the domain, it prompts me for a username and password for adding to the domain. I type a username and password, the secong I hit enter, it freezes. I tried removing the DNS entry on the server and readding it. That did not work. When it first froze, the domain was controlled by a SBS 2003 server. It is now controlled by a SBS 2011 server. The SBS 2011 server was not even booted for the first time when the initial problems started so I am not thinking it has anything to do with the new server. Any help will be appreciated. Thanks