The located assembly's manifest definition does not match the assembly reference

Question

I am trying to run some unit tests in a C# Windows Forms application (Visual Studio 2005), and I get the following error:

System.IO.FileLoadException: Co

Answer 1

In my case it was an old version of the DLL in C:\WINDOWS\Microsoft.NET\Framework\~\Temporary ASP.NET Files\ directory. You can either delete or replace the old version, or you can remove and add back the reference to the DLL in your project. Basically, either way will create a new pointer to the temporary ASP.NET Files.