0Replacing an invalid Win XP key with a genuine key

If you’ve ever been asked to fix a PC and have sub­sequently dis­covered it has a non-genu­ine or inap­pro­pri­ate Win­dows XP key installed, and you wish to update the key with a legit­im­ate key, for example when a second hand laptop has been installed with a cor­por­ate key and needs updat­ing with the OEM key from the stick­er still attached to it, you may have run into prob­lems switch­ing between OEM, Volume and Retail ver­sions of windows.

In the past this neces­sit­ated a com­plete rein­stall, but it is now pos­sible to cor­rect this prob­lem without a rein­stall. Simply down­load the Key Update Tool provided by Microsoft!
This is also con­veni­ent if you want to cre­ate and use 1 unat­ten­ded disk to rein­stall Win­dows in mul­tiple envir­on­ments. Simply build your disk with any type of disk for which you have a key and then update the key to the cor­rect key for the machine / environment.