I can't Add dll to References in Visual Studio 2010

Question

I work on WinApp in Visual Studio 2010 (With C# Language)

I want to add one dll (not system dll) to Reference.

but when I open Add Reference Window And Browse dll see under error message:

Could not load file or assembly 'W2D_D2.dll' or one of its dependencies. The module was expected to contain an assembly manifest.

this file may not be a managed assembly.

I even change the Target Platform from ".net framework 4 client profile" to ".net framework 4" but not difference.

How Can Add This dll To My Project?

Answer 1

Looks like this DLL is not a managed assembly. You can check this very quickly by trying to open it with ILSpy or Reflector.

If this is the case, you'll have to pinvoke or use com to use this dll.