Greetings --
You can perform a repair (a.k.a. in-place upgrade) installation:
How to Perform an In-Place Upgrade of Windows XP
http://support.microsoft.com/directory/article.asp?ID=KB;EN-US;Q315341
As always when undertaking such a significant change, back up any
important data before starting.
This will also require re-activation, unless you have a Volume
Licensed version of WinXP Pro installed. If it's been more than 120
days since you last activated that specific Product Key, you'll most
likely be able to activate via the internet without problem. If it's
been less, you might have to make a 5 minute phone call. You
shouldn't have to buy a new license.
Bruce Chambers
--
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