In one of our recent MVC and Angular training in Mumbai one of our students open a existing MVC core project and while running he was getting the below error.
This same code was working on the other machine. This error was because VS 2015 was not running in a admin mode. So next time you get this web.config error just run VS in admin mode.
Do not miss our next ASP.NET MVC batch in the coming week in Mumbai Andheri