My xp disc has been reinstalled on this machine soo many times I can't activate it over the net no more, I have to ring them up. They ask if it came with the pc "course it did" and is this the only machine it's been installed on "course it is" and then they give you the activation code

I'll have to do it again when I get a SATA drive for windows to be installed on, and when my "new" machine arrives