It is a simple as that I installed glimpse following this page. :
http://getglimpse.com/About/QuickStart
I then attempt to navigate to http://myApp/glimpse
I have had a very similar problem, and none of these options helped me, but I did get it working. This is what I had to do:
I am using MVC 5, so make sure you have read the latest config for glimpse for the version you are using. I should have been using Glimpse.AspNet and not Glimpse.Core
My web config looks like this:
....
....
I am using IIS Express, Vs2015 and for some reason my C:\Users\me\Documents\IISExpress\config\applicationhost.config got messed up, and had a special entry for Glimpse.
So I found and removed any entries with Glimpse in them (carefully, you might want to comment them out instead)
I think this may have happened from a really early version of glimpse been installed, and also something to do with the upgrade to MVC5, but not 100% sure why...
Hope this helps someone else.