Bathroom persia Advanced

How to re-use a generic OEM XP HOME serial key? - example serial key mount and blade

Hello All

I run a small business computer repair in the United Kingdom and more offten I was not killed with a Dell computer.

Sometimes the customer will agree that I rebuilt the machine. I have the problem that save on construction of the new machine, which costs in obviosuly want to reuse the old serial number.
For example, I have a Dell Dimension 8400 here with a Dell XP Home OEM serial number on the page. Sometimes I have to install a real copy of Windows XP Home SP2 OEM and trying to XP on the new computer age with the major OEM Dell series, but believe what? If the serial number does not work.

What is the reason? I can only assume that I am simplifying an XP Home OEM Service Pack without him? This seems a little crazy, because it means he has about 4 different CD, s and 4 XP Pro CD and what is latent with Vista is now the bad news.

Please reply if you have experienced this before and found probllem physically tired, but I do not know how the theory and practice.

There is a post here:
http://social.microsoft.com/Forums/en-US/genuinewindowsxp/thread/e89964ba-1d2d-42a4-87d7-e080879e2a41/ but many are contradictory.

Thanks
Paul