i bought a used computer is asking for user name password and domain i try to get in by safe mode nad administrator i couldn't get in i don't know what to do any more1 person needs an answerI do too

Reformat/Reinstall the O/S and start over.

You could do that, or... just drop down where it shows the domain name, and select the user, or computer name. And type in Guest for user name, and then no password... you could try typing in Administrator for user name, too. And no password for that. But if you login as guest, you will have to make changes to the accounts and add your account, to be admin.. Just right click Computer or My Computer. Pick Manage, Local Users, go to Users, add your name, then apply. Then go to Groups, Groups, Administrators, double click administrators, add your name, then apply. You will have to make a password for these, and make sure when you login, that you select the computer name account, and not the domain. it should say, (local computer), or it will have a PC name. This is the setup for Windows XP, it should be about the same with Vista or W7.