Try the following:

If your computer is still operational:

Retrieve your Windows XP CD key
http://michaelstevenstech.com/ViewKeyXP.htm

[Courtesy of Michael Stevens, MS-MVP]

If your computer is not operational:

How to Replace Lost, Broken, or Missing Microsoft Software or Hardware
http://support.microsoft.com/default.aspx?scid=kb;[ln];326246

Greetings --

   The Windows 25-character Product Key (required to perform the
installation) is stored on the CD packaging on a bright orange sticker
that says "Do not lose this number."  If it was an OEM (factory
installed) license, it's stored on a label that the PC manufacturer
affixed to the exterior of the PC case, or on the bottom of a laptop.

 To recover a lost Product Key:

   If your system still runs, you should be able to use AIDA32
Enterprise from http://www.aida32.hu/aida32.php to find the Product
Key.  (If you have a factory-installed OEM license, and haven't since
reinstalled the OS, the revealed Product Key is probably of the drive
image used at the factory and not _your_ specific Product Key;
therefore, it probably cannot be -- and definitely should not be --
used for a re-installation.)

   If it was a retail license and you have proof of purchase:

How to Replace Lost, Broken, or Missing Microsoft Software or Hardware
http://support.microsoft.com/default.aspx?scid=KB;en-us;326246

   If it was an OEM license, you should contact whomever sold you the
PC; although very few manufacturers/vendors keep records of the
Product Keys they've sold, it's worth a try before you have to buy a
new license.

Bruce Chambers

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