i am working on a computer and the persons computer rebooted and when it started back up it gave me the windows is not genuine. they have windows xp pro 2. then when i tried to restart it again thinking it was just some glitch the computer had no taskbar or start menu. it doesnt even say windows is not genuine anymore but still displays the same background. any idea what it could be? i have tried ctrl alt dlt and doing explorer in cmd.