Sorry but the answer provided does not address this problem as I am not installing on a server. I was running 4.1 & it had installed without a problem - it installed fine and was running without a problem. As the original post indicated, 4.2 starts to install but then my machine didn't reboot, so I rebooted but nothing installed, not listed in add/remove programs, so now nothing to remove. When I try the install again I get the message about other users. So I figured I would go back to 4.1 but I get the same message, so something is getting hung up in the install. I am on Windows XP. Any help would be greatly appreciated.