Microsoft recently update Microsoft Genuine Advantage software and out of the blue all my PCs from Australia deemed that my Microsoft XP Professional is non-genuine. I called Microsoft Singapore 65 6888 8899 for assistance and was asked to forward a photo of the original Software.
Couple of hours wasted on the line . I was asked to download a file and re-key in my software license .
The file is KeyUpdateTool_enu .
You can find all this here http://www.paulsxp.com/downloads.html
Anyone with this problem and require assistance please feel free to contact me.
Reference
http://www.microsoft.com/genuine/default.aspx?displaylang=en
Upon successful installation you will be able to obtain the following software free !
Windows® Defender 
Windows Media Player 11 for Windows XP
Microsoft Calculator Plus
Good luck !!
