Running Windows Updates!!!!

We are running Windows 2000-SP4 on all 400 computers at my job. Our Corporation is using a WSUS Server to force out all the wonderful Windows Updates, the problem is they do not install automatically as they should. The updates do install when done manually at each machine. We have narrowed it down to the fact that all our computers have been Ghosted using Norton Ghost 2003. My question is how do we make them update automatically? We have tried using Ghost Walker to change the SID but still no luck. Can anyone help!!!!