[slodave]

Are you sure that the cd was for that computer? Service packs do not make a difference. Also, if you had the CD in the drive when you rebooted and the cd was a valid OEM or Retail version of XP, it would not matter. The initial install screen allows you to format or reinstall over an existing version and does not care what was on before.

User profiles can become corrupt and are difficult to repair. I have a client that went through the same thing. The profile was slow, I could not fix it, so I just created a new one.