I had this error on a client site today when deploying a Windows XP machine that had been in operation for many years into an SBS 2003 R2 network.
I tried to action the suggested fix from the error message, but this did not resolve the issue. I then dug deeper into it by using the SBS Client Setup Log file and as you can see below found it was related to some files on the desktop of the computer.
I deleted those files and ran the connectcomputer wizard again. It still failed, so I reviewed the log file again and found that this time it was related to files in the users temp directory. I deleted them and it worked fine. The secret here is to ensure that you review the Client install log files to know what is causing the problem.
The file is called SBSNetSetup.log and it’s located on the client computers hard drive under C:\Program Files\Microsoft Windows Small Business Server\Clients.