I have followed the answers provided by very similar posts as you will see in the step by step listed below.
Razor view Type does not inherit from 'Syst
Do not delete the webconfig, is a very important file in your views!!!
Instead, do this:
Enable "View all Files" in the web project that is failing, and search for a file that seems correct but is not included in visual studio, and delete it. If it fails in your deployment folder, try to clean the folder as well, and re-deploy the site, you might have unnecesary files that might cause the same problem.
In my case, at the root of the webproject I had an extra copy of _ViewStart.cshtml (excluded from the project), I deleted that file, and that did the trick.
Hope it helps, let me know if this solve your problem as well.