A common problem when you try to install karma, mean stack or other node modules that depend on gyp module. You see following message:
TRACKER : error TRK0005: Failed to locate: "CL.exe". The system cannot find the file specified. [d:\worek\gitHub\meanPlayground\play ground\node_modules\bufferutil\build\bufferutil.vcxproj]In many places you will see that you are missing VS2013 compiler, and you will be asked to install Microsoft Visual Studio Express 2012 for Windows Desktop. Do not do it if you are running VS2015, just add feature in VS: Common Tools For Visual C++ 2015.
Under the hood it will still install multiple 2013 components - ech, and the year is almost 2016.