here is a little information from winbeta.org
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Since the release of Windows XP Professional, Microsoft has discovered that the vast majority of illegitimate copies in use are using a small handful of leaked \"corporate\" keys. In an effort to thwart these illegitimate users, Windows XP Service Pack 1 (and possibly all future updates) will not install on systems using these keys, and it is unclear what additional steps Microsoft may take until SP1 is officially released. Legitimate licensed users of XP Professional should be unaffected, however there are a number of different ways one of these leaked keys can find it\'s way into an otherwise legal environment and cause serious deployment issues. Here\'s how to check if your systems are using a leaked key, and how to change the product activation key if they are.
WinBeta.org
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http://www.winbeta.org/modules.php?name=Ne...order=0&thold=0this article goes on to tell you how to change your PID with your CD key and so on.
But after a while SP1 is out, is this good, or just more of a pain.
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You can also look up \"Blocked product key prevents XPSP1 for installing – Q326904\"
And there are other already known issues with SP1 and building, if you would like a bigger list just let me know and you shall recive.
