Reference disappear upon debug/build (C#, VB.NET, VS2010)

Question

I am using the MagicLibrary for a few components. I knew it was written in Visual Studio 2003 and recompiled it in Visual C# Express 2010. It compiled just fine

Answer 1

Check that you are using the .Net 4 framework and not the client profile version

You find that setting when you right-click on your project, choose properties. And under application there is a setting for target framework. If you have chosen the .Net 4 framework Client Profile, then this behavior that you described can happen