I began receiving this error after upgrading to .NET Beta 2 …

System.IO.FileLoadException: Mixed mode assembly is built against version ‘v1.1.4322′ of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information.

I suspect it’s the Managed.DirectX DLL that I’m using.

Adding the following to the application config file appears to have solved the problem for now:-

<configuration>
<startup useLegacyV2RuntimeActivationPolicy=”true”>
<supportedRuntime version=”v4.0″/>
</startup>
</configuration>