Eh?! Window's won't activate anymore

[Atari]

Hi all,

Got a slight problem here with my Windows XP Activation. Basically, when I started university, I received an email from the MSDN Academic Alliance Software service. It outlined that MS and my university had some kind of agreement where students could download copies of Windows XP and other software such as Visual Studio.net. Needless to say, I downloaded Windows XP from the site and installed it on my machine.
It activated fine that time (September), I could connect to Windows Update and download all the security patches whenever I needed. Everything was fine, I reinstalled my computer around December and it activated fine then too.
Yesterday however, I went to reinstall Windows as I do every few months, but when I logged onto Windows Update, I got a message saying that my CD Key wasn't valid. I've been using the site for last few months without any trouble at all, and today I get a message saying that the key isn't valid.

The hardware in my computer hasn't been changed since I started uni, everthing is exactly how it's been the last few times I've activated.

Anybody got any idea's as to what might be causing it?

Thanks for any input

 

[Atari]

Thanks for the replies guys, it's been doing my head in trying to find who I'm supposed to talk to about getting it sorted. I'll have to wait until Monday to speak to the Admin department about it.

I reinstall every few months to keep the system running smooth, after a while I find I have loads of processes going on which slow my rig down so I end up doing a full reinstall.