I dont know what happen

[757200ba]

I have this old pc the MB is Asrock K7VT4A Pro.
2 days ago every time i start the pc it get's to windows and it asks me for a password ( it never had one), i tried to go to cmos so i can configure so it starts by reading the cd rom and now it also asks for a password, i tried to reset the cmos, with and without battery  and nothing it still asks for password.Any ideas to repais this?  

[NickN]

sounds to me like something got into this machine and has messed with the accounts..

Are you saying it asks for a password and you can not get in, or are you saying it asks for a password and and you can bypass it like a nag?

If you really need a password to get into Windows and you never set that up or made any account changes then you have a nasty critter on that system