March 2007 Windows Vista Application Compatibility Update

The March 2007 Windows Vista Application Compatibility Update is a package of software updates that address common application compatibility issues in Windows Vista.
When you try to install and run certain legacy games or applications in Windows Vista, you may experience one or more of the following symptoms:

-) The game, the application, or the firmware may not be installed correctly.
-) The game, the application, or the firmware may cause system instability.
-) The primary functions of the game, the application, or the firmware may not work correctly.

http://support.microsoft.com/kb/932246/en-us