Modern apps over proxy authentication

Your Windows 8 app store Modern apps may not connect to their background services behind an authenticated proxy. This code logic might help to make your Modern application code proxy authentication aware...

 HttpClientHandler handler = new HttpClientHandler();

 handler.Proxy = WebRequest.DefaultWebProxy; 

 handler.Proxy.Credentials = CredentialCache.DefaultCredentials;

 HttpClient client = new HttpClient(handler);