Re-entering product key

troruud

Distinguished
Apr 2, 2011
3
0
18,510
Hello,
Microsoft tells me the product key I entered on installing XP belongs to a blocked volume license, and claims I have an illegal copy, but it turns out the key I used belonged to my old machine, and so I want to enter the key I got with my present machine instead. Do I have to reinstall everything from scratch, or is there some way to enter the new key, after XP and a ton of software has been installed?