Unable to log on: Netlogon Not Running

Win2K Pro connected to domain suddenly displays error that the Netlogon service is not running on the PC. In attempting to remove or reinstall TCP/IP, error ‘Could not install the requested component. A system call that should never fail has failed’. This error occured on five computers. TechNet is NO help. I have ghosted four which fixed the issue. The fifth I cannot erase. Norton detects no viri. Will reinstall SP2 tomorrow.