I also experienced this error when working with CMake:
No CMAKE_C_COMPILER could be found.
No CMAKE_CXX_COMPILER could be found.
The 'warning' box in the MSDN library article Visual C++ in Visual Studio 2015 gave me the help that I needed.
Visual Studio 2015 doesn't come with C++ installed by default. So, creating a new C++ project will prompt you to download the necessary C++ components.