Forbidden You don't have permission to access / on this server IIS

Asp.NET website published on IIS on some server. The site working correctly, when browsing this website from the server which contains it the site working without problem. I browse with Url http://localhost/TR/Login.aspx every thing ok.

When I am trying to reach the website from the outside of the server using its ip address I am getting the following error

Forbidden You don't have permission to access / on this server.

Before giving a suggestion, keep in mind that I checked the following

1. firewall of the server is not working
2. inbound/outbound rules have been created for the port of the website in the firewall
3. I added a binding to the website which contains the IP address of the server and specified the port
4. The Security tab of the website contains IIS_IUSERS exists and all the permissions for it are "allow"