Hi, I still don't have clear if your project is compiled for .NET 2-3.5 or 4.x. I assume it's the former, so let's exclude x64 and .NET 4.0. Please also try to use a more recent version of NUnit as you're still using 2.5 (the most recent is 2.6.1). Then please run nunit-console-x86 under .NET 2.0 (remove the .config changes basically) against your project compiled for Any CPU (or x86) and paste what you see in the EventLog. If you still get: Could not load file or assembly 'ClassLibrary1' or one of its dependencies. The system cannot find the file specified. Please provide the fusion log. Simone On Wed, Oct 10, 2012 at 10:49 AM, Mun Wai Chan