Today when writing tests for a new project built using VS2010 I had an interesting problem: NUnit would not run my unit tests because the assembly that contained my unit tests was compiled using a newer version of the .NET runtime. There are several solutions to solve this issue from downgrading my project to use earlier version of .NET to migrate my unit tests to MSTest but luckily for me no such drastic move was needed. The new NUnit (2.5.x) have support for running tests using .NET 4 it’s just...