C++ Transition Guide for 4.18

@RyuMaster as well (since you had the same issue).

The fix is not to “Build Solution” on the engine, simply build the UE4 project itself (it’ll bring in any needed dependencies). That issue is specifically a Mac tool that is included in the solution by default and needs to be removed - but, still, you shouldn’t “Build Solution” by default on the engine anyway, it’s not needed/required.