Visual Studio 2015 installer hangs during install?

Question

I downloaded the full ISO for Visual Studio Ultimate CTP 6. The installation program got to about the 90% mark, gauging by the progress bar, and just stuck there. There wa

Answer 1

In my case UAC was disabled (the infamous regedit trick) and so the installer clearly could not handle it.

You could revert back to UAC for the installer, or simply try launching it as admin, it worked for me.