This particular error caused me some headaches so I decided to blog about it in the hope that it'll help some other poor soul! I have a pretty standard MVC 3 project that uses Entity Framework Code First for handling the database side of things. I decided to update my project to ensure it was using the latest version of all of the packages in use on my project (ninject/entity framework/etc). This particular project was using Entity Framework v4.1, which I had previously updated using NuGet without any problems, so I decided to download and install the latest version from NuGet - ver 4.2.