I can't go stuck in the login window?

Ok my PC got a Virus and Spyware and i try to install avast anti virus in safe mode to repair my computer.

when the anti virus call me to reboot my computer i say yes and then i got stuck in the login window.

WHen i try to press the administrator account it keep on login and off and don't want to go the my window desktop.

Please help and THANK YOU for the Answer.

I can't go stuck in the login window?virus removal

ok ive had this problem the chances are you have about 700 virus's running through your computer.

or more.

so i want you to boot up your computer tapping the f10 key if your on windows xp or f2 key or f8 key try them all depending on what you have.

when you find the option system restore, restore your computer to an earlier point before you got the virus.

and if that does not work.

wipe your hard-drive clean, then reinstall the c:/drive

edit: ok restoring will only take you back to the date that you restore so all saved work in the system will be lost from that point.