I have a 'borrowed' version of XP pro. When I tried to update to SP2, the new Windows authentication tool determined that my version is not good but allowed me to downlaod it anyway. When I did, the system became VERY unstable. My CPU usage is at 100% and I get blue screens all teh time and it is VERY slow. I uninstalled SP2, but it didn't help... I took my computer into the shop and the employee explained to me that Microsoft is messing with peoples systems when they find a computer with a 'borrowed' key. I found it hard to believe... The tech tested my RAM and that was fine. I explained also that I could not install programs because the MS Installer wasn't working for me... GRRR! Is this true??? Now my dilemma, do I buy a copy of XP and use that... will that solve my problems, or is it a different matter altogether? I know I am better off with a new version of XP... My next question is: When I was talking with the tech, he gave me a disc with XP PRO SP2 on it (I believe it is slipstreamed)... If I format my computer, and then reinstall with that new disc, what do I do about a key...? Can I use that key? He said I would have to get a new one. the disc he gave me was the one they use for troubleshooting, and because I had so many problems he felt bad and just threw it in for me. (nice guy) but, now I think I am stuck trying to find a key... And a legitimate one at that... How would I do that? Please help, I am not a neophyte, but far from a super tech! Thank you for your help, Matthew