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
OEM versions of Windows XP are not supported by
Microsoft. Only "retail versions" of Windows XP are
supported by Microsoft. Microsoft cannot issue you
a replacement Product Key for an OEM version.... only
if it were a "retail version".
--
Carey Frisch
Microsoft MVP
Windows XP - Shell/User
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| I installed XP on my desktop. Recently bought a new hard
| drive. Tried to reinstall XP but it asks me for a
| product id code. I purchashed it from a small retailer
| that doesn't have the number, Is it possible to attain a
| number?