|do i need to reformat it?|
No, just tap f8 on bootup and select safe mode. Go to control panel and select user accounts.
You will see a password protected user in there that was installed with an auto-update with I think frame network or machine user...it's been awhile since I fixed this, sorry, I'm doing it from memory. If you get stumped on that USERNAME, post back the username that is password protected and I'll verify the removal.
Just delete that account and then reboot. It will not ask you for your login again. Good luck
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