The root folder of the Web server (for example, \inetpub\wwwroot) might contain a Web.config file that has settings that ...

The root folder of the Web server (for example, \inetpub\wwwroot) might contain a Web.config file that has settings that apply to all Web sites that are running on that server. At the application level, another Web.config file might exist that defines settings for that application. Other Web.config files also might exist in subdirectories of your application that specify settings that apply to the resources that are contained within those subdirectories.