Bad key error message (with valid key)

[monty]

I'm getting the bad key error when I try to change my key from the installed version of Windows Professional, to the key on the back of my laptop. I have a VAIO VGN-S28GP, and the key I want to use is valid as it works with the version of windows that shipped with the laptop. I have installed a vanilla version of Windows Professional without all the VAIO bloatware, and just want to change to key to my personal copy. I've tried it in Safe Mode to no avail.

Any help would be appreciated.

[Imran]

Why would you like to change? wanna use same key on two different systems?

Windows XP has many different Versions within an version, like OEM Professional, and more, no cd key of each other can be interchanged.

[Ben Schulze]

I have a simular problem when I try to change the key of XP Pro Sp1 or SP2 (OEM versions). Who can help me?

[Imran]

Probably this article might help you.
http://www.winkeyfinder.com/force-an...e-installa.php

[Radiation]

Good article