I had a bad fan in my Dell computer that I replaced. I am running Windows 2000. Now when I boot up i get an error "Winnt\system32\config\system.ced" file may be corrupt or missing. I use this computer to operate the HVAC for my entire office building so reformatting is out of the question. I am afraid to jack with registry from DOS unless I can better sounding results than what Windows help has to offer. Can anyone help. I don't appear to even have this file.

Try this:

http://www.houseofhelp.com/v3/showthread.php?t=17398