Not work with proxy

Not work with proxy.

Sample Fix - add work with DefaultCredentials
(
Put this in application configuration file.
--<?xml version="1.0" encoding="utf-8" ?>
--<configuration>
  <system.net>
    <defaultProxy useDefaultCredentials="true" />
  </system.net>
--</configuration>
). 
And add options to manul edit proxy settings.
