This issue affects Windows XP Media Center Edition 2002.
If you install this release candidate on a computer running Windows XP Media Center 2002 with XP SP1, Windows XP Media Center may malfunction.
To avoid this, install Windows XP SP2 before you install this release candidate.
If this issue has already occurred, uninstall this release candidate, install Windows XP SP2, and then reinstall the release candidate.
http://download.microsoft.com/download/c/d/8/cd8cc719-7d5a-40d3-a802-e4057aa8c631/relnotes.htm