A friend of mine runs a preschool and has 3 old P3 computers that the kids use for simple games. He asked me to clean the hard drives and update the OS. Somehow, they have XP Pro installed - illegal copies that cannot be updated. He has disks for NT Workstation legal copies (two have never been opened). I want to take the illegal OS off and put the legal OS on. So far, I havent figured how to do that and going backwards doesnt seem to be covered when I did a Google search on how to do that. I tried format c: from XP and it does not want to do that, even from safemode and a prompt window. I tried booting from the CD drive and the install program for NT Workstation does not know how to do what I want either. Suggestions?