[pnelsonAG]

I have never seen such error before.

Have you added reference to SharpDX.dll, SharpDX.DXGI.dll, SharpDX.Direct3D11.dll and SharpDX.Mathematics.dll to your project? (Note that the SharpDX.Mathematics.dll is only needed when using SharpDX v3.1 and is not needed for v2.6.3)

Is your project's target framework set to .Net 4.5 or newer? The SharpDX v3.1 can be only used on .Net 4.5+. If the target framework is 4.0, then you need to use SharpDX 2.6.3.

It is .Net 4.5. I have fixed the problem by explicitly adding the references to the SharpDX libraries as you suggested but I don't understand it. I didn't have those in the project when I was using the evaluation version of the AB4D library and I haven't changed a single line of code in my source code.

I have added an attachment of a pair of screenshots of the Visual Studio Solution Explorer "References" section for the project when it was using the evaluation version versus the commercial version to prove that the SharpDX libraries were not explicitly included. The one on the left was when I was using the evaluation version - it built and ran fine. The one on the right is the current version, showing the SharpDX references needed to get a good build. Anyway, everything seems good now.