This documentation covers the Windows Media Format 7 SDK through the Windows Media Format 11 SDK. Individual methods, structures, functions, and enumerations include version requirements in their reference topics.
The Windows Media Format 11 SDK is supported on Windows Vista and Windows XP only.
The Windows Media Format 9.5 SDK is supported only on Windows XP. If you write an application based on the Windows Media Format 9.5 SDK, your application will not run on any other operating system.
A few features of the Windows Media Format 9 Series SDK also require Windows XP. The individual reference topics relating to those features call out that requirement.