MVC routes. RouteExistingFiles=true setting in the development environment is invalid-CodePudding

 
Public static void RegisterRoutes (RouteCollection routes) 
{
Routes. RouteExistingFiles=true; 

Routes. IgnoreRoute (" {resource} axd/{* pathInfo} "); 

Routes. The MapRoute (
Name: "Default", 
Url: "{controller}/{action}/{id}", 
Defaults: new {controller="Index", action="Index", id=UrlParameter. Optional}, namespaces: new [] {} "Web. Controllers" 
); 

} 

Configuration file Settings are 
 

IIS Express configuration is as follows:

After the following configuration, development environment, as long as the file exists, or can return, but released to IIS is good, what reason be