You'll need to perform a "repair install" using your new
Windows XP CD and Product Keys for each computer.
How to Perform a Windows XP Repair Install
http://michaelstevenstech.com/XPrepairinstall.htm
[Courtesy of Michael Stevens, MS-MVP]

Signature
Nicholas
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| I used an standard retail box to upgrade my pc's to
| windows xp pro. I then ordered the Open License with
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| do any updates it fails.) So I have 7 more pcs to do and
| I am not sure the best way to proceed.