When I purchased my pc 6 yrs ago it came preinstalled with windows 2000 as the Os. A couple yrs ago a buddy installed windows xp pro (unlicensed version). Now of course I cant get any windows updates and the company I purchased my pc from has gone out of business. Is it possible to reinstall windows 2000 from my harddrive without the CD. By the way my buddy did not create a system restore date before he installed the xp pro over windows 2000. My mistake.