Few days ago Microsoft released a Microsoft Virtual PC 2007 with SP1. This update for Microsoft Virtual PC 2007 includes support for the following additional Host and Guest Operating Systems:

Additonal Guest Operating System support:
Windows Vista® Ultimate Edition with Service Pack 1 (SP1)
Windows Vista® Business Edition with Service Pack 1 (SP1)
Windows Vista® Enterprise Edition with Service Pack 1 (SP1)
Windows Server® 2008 Standard
Windows XP Professional with Service Pack 3


Additional Host Operating System support:
Windows Vista® Ultimate Edition with Service Pack 1 (SP1)
Windows Vista® Business Edition with Service Pack 1 (SP1)
Windows Vista® Enterprise Edition with Service Pack 1 (SP1)
Windows XP Professional with Service Pack 3

Download from here

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