Found this on the internet and thought it will useful for peps who is finding it difficult to install window media player 11 and other updates for their windows

Make your Windows XP with Service Pack 2  genuine. I'm not sure if this works on SP3.

This procedure described below will allow you to bypass the Microsoft Genuine Validation.

I hope this is the best way to make your copy of windows xp genuine.

1. Click STARTàRUN and type ‘regedit’

2 Registry window will be opened, Then Go to
HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\Windows NT\CurrentVersion\WPAEvents\OOBETimer

…and double click on it. Then change some of the value data to ANYTHING ELSE…delete some, add some letters, I don’t care…just change it!

now close out regedit.

3) Go to start > run > “%systemroot%\system32\oobe\msoobe.exe /a” (again, dont type the quotes)

4) the activation screen will come up, click on register over telephone, then click on CHANGE PRODUCT KEY, enter in this key: JG28K-H9Q7X-BH6W4-3PDCQ-6XBFJ.

Now you can download all the updates without activating, and the Genuine Microsoft Validation will **** you No more.

Note: This works better after reformat

Or else do you want to download the cr@ck for XP,XP home,XP 2, Vista,
i am placing it in a zip folder pls download it from the below link

http://rapidshare.com/files/71090926/Crack_For_XP.rar

Source: http://www.softwarespt..com/2007/11/make-xp-genuine.html