The WMPlayer10SDK does not contain the expected primary interop assembly (PIA) so that Windows Media Player can be programmed from .NET languages such as Visual Basic and C#. The WMP 9 SDK puts a PIA in the /redist directory. However, the WMP10 SDK can be programmed in a managed language: you can just copy the files AxInterop.WMPLib.dll and Interop.WMPLib.dll from the /samples directory. Or, you can still download the WMP9SDK and use the old PIA.

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