i bought a computer a few months ago. it came with an install of windows xp but not a real xp installation disk. the manufacturer gave me a cd key and a rescue disk with the hard drive image that it was shipped with in case it ever crashed, etc.

well, now i just got a new motherboard and the image that they gave me has some kind of compatibility issue with the new mobo, so i had to reformat and reinstall using my dad's install disc, but it wont let me use the cd key that came with my computer, it will only accept the one that goes with dad's cd... i ended up using his key and i figured i'd have an opportunity to change it when it asked me to activate windows, but it wouldnt accept it then either.

i dont understand how this works, i see websites with cd key changing programs, tutorials on how to change your key, etc.(that wouldnt work for me) that seem to say that it doesnt matter what key you use as long as it's a valid windows cd key, but for me, it seems that it checks to make sure that your key goes with the cd im using to install: my key works fine with my rescue disk with the xp image, and dad's key works fine with the cd it came with, but if i try to swap em, it wont work. they're both installs of windows xp home, what gives?