http://blogs.technet.com/windowsvista/archive/2006/07/19/442570.aspxCheck this out: we've just today launched a page that clearly explains how to upgrade your existing system in-place from a legacy Windows OS to any Windows Vista version; or, in the case of certain systems, whether you'll need to perform a completelyCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.technet.com/windowsvista/archive/2006/07/19/442570.aspx#445112Sat, 05 Aug 2006 18:07:55 GMTd5e57398-b9ef-4490-9955-07cbb4e4a80d:445112yuhongUpgrades from XP Media Center to Vista Home Premium should not be allowed because it is not a true subset of XP Media Center because it is based on XP Professional, not Home Edition