Since Microsoft released vs2015 update 2, I found that repairing the vs2015 installation involves a mandatory upgrade, requiring removal of the 2015u1 versions of C++ 2015 redistributable x64 and x86 and reboot. There is no longer an option about which Windows Kits version is to be used, and (at least on Windows 10) it seems to install a suitable one by default. I'm still waiting for a chance to reboot my Win8.1 and complete the repair.
I remember but can no longer find the post here which said that ICL -Qstd=c++11 and c++14 are likely not to work with vs2015u2 until ICL 16.0.3 is available. I have made some successful tests of VS2015u1 and ICL and ifort 16.0.2 where I didn't use -Qstd=c++....