Visual Studio 2015 Broken Razor Intellisense

Question

After installing and then repairing my VS2015 instance I still cannot get intellisense (server side) to work in my MVC views. I get alerted by message promp

Answer 1

I've posted this answer on another SO question, just because I want to prevent people wasting the time I've just wasted. My problem was that I'd added files to a project, but not included them. So I chosen to show all files:

then chose to include folders:

The problem only shows up when you open an MVC website as a project, and not when you open it as a website directly.