http://blogs.msdn.com/usisvde/archive/2008/05/14/windows-presentation-foundation-update-brings-smaller-footprint-better-performance.aspxThe new version of .NET Framework Service Pack 1 includes an update to Windows Presentation Foundation (WPF) that includes a slimmed down version called Client Profile. Instead of more than 50 megs that had been required on Windows XP, now you'll haveen-USCommunityServer 2.1 SP1 (Build: 61025.2)