Windows 10 will not accept administrator's password, or even allow me to select F12, or F2. Can not even tell you if the Num lock key is on or off. Because the keyboard light appears to be for the entire key pad. Never the less It doesn't work. I am totally locked out of my PC. I tried Microsoft logon, however it will not work on my Dell PC that is of course locked. There must be a solution? Do now have a backup disk or password disc. Please help!