Your PC's Windows Logon registry Value is changed... Pls do the below steps for restore the old registry value that will work on your PC
Enter the Recovery Console
Boot the system using the Windows XP CD-ROM. In the first screen when the Setup begins, read the instructions press "R" (in the first screen) enter the Recovery Console. Type-in the built-in Administrator password to enter the Console. You'll see the prompt reading C:\Windows (Or any other drive-letter where you've installed XP)
(rename the current registry files just incase you want to rename them back)
ren c:\windows\system32\config\software *.old
ren c:\windows\system32\config\system *.old
(access the System Restore backup copies of the registry files)
cd\system volume information
and then: cd RP?? e.g. cd RP63 (pick the latest Restore Point folder it should be the highest numerical value from the directory list)
cd snapshot (if this folder is missing "File not found" you need to pick another recent RP folder)
(replace the system registry files using the backup copies)
copy _REGISTRY_MACHINE_SOFTWARE c:\windows\system32\config\sofware
copy _REGISTRY_MACHINE_SYSTEM c:\windows\system32\config\system
(Now reboot Windows should be running back to normal.)
Please post back and let us know if the above steps worked out.
if it does not I suspect that the winlogon.exe in the machine was infected and was picked up in the scan process.. the steps to replace those can be tried next if you machine still does not work
Okay I am thinking I am hosed. I have no System Restore or Back up files. Is there any help for me? Feeling very defeated. I am pretty sure everyone is correct and the logon file was corrupt, is there anyway for me to fix this without the System Restore or a Back up file?
That is the situation, You need to Reinstall the Windows...
Note If Windows XP was preinstalled on your computer, you may need the installation CD to reinstall. Contact your computer manufacturer to make sure that you have the installation CD for a repair installation.
To reinstall Windows XP by starting your computer from the Windows XP CD, follow these steps: