This is my web.config which has some tags for blocking Ipaddress
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For Windows 10 and Visual Studio 2015 note that the ApplicationHost.config file has been relocated to the .vs\config folder in your project's folder hierarchy. You will need to edit the project specific version of the ApplicationHost.config file found there with...
If you only edit the ApplicationHost.config located in your Documents\IISExpress folder this will not affect your existing application (MVC5 appl in my case).