Re-installing on second computer after formatting

[NATHAN]

Hi ,i just got my update cd today and have gone to update hoster but it again is saying that there is something wrong and asking to contact you. I have changed nothing at all. I am running winxp home. Again i say the protection i over the top a bit. I seem to have this problem every time i re-install or update. PLEASE HELP ME ,i have a show to do in a couple of hours time.

thanks nath.