Error Rendering control - [A] cannot be cast to [B] in the context LoadNeither

Question

I am working on a composite control and this requires me to open multiple Visual studio IDEs and add the control on pages.

This causes Visual Studio to create multip

Answer 1

In order to make this work you'll need to put the control project and the test project in two different solutions. The problem is unique to issues where you have to debug another running instance of Visual Studio. You'll see this if you work on Visual Studio add-ins, too.