The setting of the BypassProxyOnLocal property determines whether WebRequest instances use the proxy server when accessing local Internet resources.
If BypassProxyOnLocal is true, requests to local Internet resources do not use the proxy server. Local requests are identified by the lack of a period (.) in the URI, as in http://webserver/, or access the local server, including http://localhost, http://loopback, or http://127.0.0.1. When BypassProxyOnLocal is false, all Internet requests are made through the proxy server.
Requests to a local host with a URI that contain a period use the proxy. To avoid using a proxy in these cases, create an entry for the host in the BypassList.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)