Strange Error - CS0012: The type x is defined in an assembly that is not referenced

Question

The type \'x\' is defined in an assembly that is not referenced. You must add a reference to assembly \'abc123\'.

I have a .NET 2.0 web application that references m

Answer 1

I found that if type x is actually a class in your App_Code, dirtying it and re-saving often forces the web app to recompile and solves the problem.