XP Login/Logout Loop

Working with a friends Dell Dimension B110 computer with SP3.

Computer has been running fine for them until last week. Now every time they login under any of the accounts it seems to log them in -- flashes the wallpaper then immediately logs them out (saving settings, etc...) and back to Welcome Login screen.

Here are some things that I have tried based on my googling:
1. Safe Mode -- same result as above
2. Last good configuration settings -- same result as above
3. Safe Mode command prompt -- same result as above
4. ctrl-alt-delete at windows screen logging in old style -- same results as above
5. boot from xp cd logging into recovery mode -- copied the userinit.exe to wsaupdater.exe -- same results as above

Additionally while booted in from xp cd I did tool around abit, but recieved some access denied messages to directories like "program files" and "Documents and Settings".

Any suggestions on how to log into this box are greatly appreciated.

Thank you.

 

I found a solution and am now able to login. I am going to run through the scans in the read me section of this forum now and see if this was in fact malware or not. According to the source for the solution there are non-viral reasons this may have happened.

Here is the link with the info that helped:

http://www.paulscomputerservice.net/index.php?body=./os/autoLogoff.php