When using Visual C++, fixtures are included in a DLL. The AppFixtureMaker creates them, and is located in the DLL with the fixtures. CppTestTools also provides FitServer.exe which is the main for the FitNesse Server. Your application has to provide a bat file that sets the path, so that your DLLs can be found, and invokes the FitServer. See HomeGuard/test for an example. The COMMAND_PATTERN in your FitNesse tests must invoke that bat file. The main page of the HomeGuard fitnesse pages has an example of the needed COMMAND_PATTERN