Restart immediately after login

I have a computer that was unplugged by the cat. Its basically used as a fax server. When I login it immediately restarts, right after i enter the password. I was able to get into safe mode and I changed the startup in msconfig to diagnostic start up and then restarted and it does the same thing. Any idea of what I can do or the steps that I can take? I do have a ghost image of this pc but I really don't want to resort to that option.

 

Start the computer using Safe Mode, and do the following ...
Use the Windows Error checking utility (Check Disk), with the options to scan the disk surface for errors, and attempt recovery of data and repair the disk.
Open "My Computer"
Right-click on the drive that you wish to check (C: drive/your System drive) > Properties > Tools > and in the "Error checking" section, click on "Check now".
Place a tick in both boxes > Start.
A message will notify you that a restart is necessary: Click OK, and close all windows.
Re-start the computer. The disk will be checked when the system boots.
This test will take some time to run and at times may appear stalled but just let it run.
When the disk check is complete, the system will re-start automatically and load Windows.
If any errors were found, it may be prudent to repeat "Check Disk".
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This just about sums up chkdsk /r
Quote: "wow thanks, quick way to solve it."
http://www.bleepingcomputer.com/forums/index.php?s=&showtopic=274837&view=findpost&p=1520848

 

Problem Solved. Turns out it was a Virus that symantec partly removed but the other part was still causing a start up issue. Either way I did run the chkdsk like you suggested and did find 1 error so that was fixed atleast. Thanks! +rep!