I often run test codes that reference methods of business class and the class is compiled and stored in GAC. Sometimes, I update the method but NUnit keeps running the old code. What I did was
But still it did not work. I slept on it and the next morning, I remembered I didn't restart NUnit and NUnit might hold the old assembly in its own memory. I closed NUnit and opened it, and the new method was loaded. Fantastic.
So, when you changed your method but can't see it working, restart NUnit!
Added in 3 days later
To ensure NUnit loads the newly compile dll, please do