I have logging class which are using everywhere. I want to Mock this class for all tests. And i tried to use AssemblyInitialize but got problem. I have simulated this problem with JustMock.ElevatedExamples.AdvancedUsage examples: 1) Add BaseTest class [TestClass] public class BaseTest { [AssemblyInitialize()] public static void AssemblyInit(TestContext context) { Mock.SetupStatic(typeof(Common1), StaticConstructor.Mocked); // Arranging: When the static(Foo.FooProp_GET) property is called, it should return expected. var fakeUsed = Mock.Create<LogWriter1>(Constructor.Mocked); Mock.Arrange(() => Common1.Log).Returns(fakeUsed); } [AssemblyCleanup] public static void Cleanup() { //clean up stuff here } } public static class Common1 { static Common1() { Log = new LogWriter1(); } public static LogWriter1 Log { get; set; } } public class LogWriter1 { } 2) When run test from VS - all ok 3) When run from command line it is not working. Show Message box "Process Starts Now". SET JUSTMOCK_INSTANCE=1 SET COR_ENABLE_PROFILING=1 SET COR_PROFILER={B7ABE522-A68F-44F2-925B-81E7488E9EC0} "C:\Program Files (x86)\Telerik\JustMock\Libraries\JustMockRunner.exe" "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\MSTest.exe" /testcontainer:"D:\test\CSExamples\JustMock.ElevatedExamples\bin\Debug\JustMock.ElevatedExamples.dll" How i can mock logger for all test? It is static public property. I use MS Test + VS 2015.