System.Net.WebClient doesn't work with Windows Authentication

Question

I am trying to use System.Net.WebClient in a WinForms application to upload a file to an IIS6 server which has Windows Authentication as it only \'Authentication\' method.

Answer 1

Try going into IE's options and explicitly add the site to the Intranet Zone. Then re-run the program. You should also not run the program from an administrator login. This may trigger the Enhanced Security Configuration for Internet Explorer.

It could explain why you can hit the site with Firefox and Opera, but not with IE or WebClient.