Hi, my computer has been afflicted by a number of viruses (e.g Vundo, Vundo H) which Norton Internet Security 2008 has not been able to address. I followed an advice from one of your other posts ("Virus/Spyware, need help") and used MalwareBytes to remove the viruses. 72 infected files were found and removed. However, following the reboot of my comp. I am unable to log on. It keeps logging me off every time I attempt to log on. Not sure if some vital file has been deleted during the cleanup. Would very much appreciate your help.

Can you boot into safe mode? Restart your computer After hearing your computer beep once during startup, but before the Windows icon appears, tap the F8 key continually; Instead of Windows loading as normal, a menu with options should appear; Select Safe Mode, then press "Enter". Let me know if you can.

As you suggested, I have tried booting in Safe Mode, Last Known Good Configuration and also using the other options available, but it still keeps logging me off (with the following text showing "logging off, saving your last settings") when I click on the user icon to log in (or any other icon including the Administrator). Another problem is that I do not have XP boot disk. I would appreciate any other suggestions.