Grab this if you want to use the Expression Encoder 2 SDK with Visual Basic

Microsoft Downloads - Update for Microsoft Expression Encoder 2 (KB955622)

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The Expression Encoder 2 Update enables the Encoder 2 classes to appear and to be used within your application when you are using Visual Basic.NET with the Expression Encoder 2 SDK.

Note: After you create a Visual Basic.NET application by using Expression Encoder 2 with the update installed, the application will work with other installations of Expression Encoder 2 without the update needing to be installed.

For more information, see KB article KB955622. [GD: At the time I posted this the KB article was not available]

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Microsoft Downloads - Microsoft® Expression® Encoder 2 SDK

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The Expression Encoder 2 SDK includes documentation, samples, and code to help you work with the Expression Encoder object model and extend the functionality of Expression Encoder 2.

The Expression Encoder 2 Object Model (OM) parallels the features exposed by the Expression Encoder 2 user interface and command-line application. It is built on top of multiple media technologies, including DShow, Silverlight and Windows Media.

This download includes:

• IntelliSense for Expression Encoder 2
• SDK documentation, including API reference
• Code samples

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I can see a day where I might need this…