If it's a Windows password try clicking Cancel. If it's a BIOS
password, you have a problem. If you can find the system or
motherboard documentation, it should tell you how to reset the BIOS
password. This probably involves shorting a pair of contacts on the
motherboard. If you can't find that documentation, try removing the
BIOS battery for a moment or so. BUT FIRST go through the BIOS setup
program and write down or print out the settings. It will forget
EVERYTHING when you remove the battery. Anything that's not the
default value will have to be reset.