Microsoft has released an update on the MSDN subscribers website, which resolve the expired notification when launching Media Center problem in Windows Vista December 2005 CTP

If you try to open Media Center or access any Media Center functionality in the Windows Vista December 2005 CTP, the following notification will display: This Trial Version has Expired and Can No Longer Be Used.

Please install this update to enable use of Media Center and Media Center functionality in Windows Vista December 2005 CTP.

Important: Only install this update on the Windows Vista December 2005 CTP. This update will break all previous versions.

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