Http Error 407 when trying to sign on with Windows Login


Hi there,

I am wondering if anyone has knowledge of how Duo Windows Login works through an HTTP Proxy. It looks like it is connecting directly and does not leverage any of the default Windows IE proxy definitions or user credentials. I am saying this because there is documentation that says it uses the “netsh proxy” settings and also via the “HttpProxy…” registry entries.

We are having a problem with signing on using Windows Login behind a Blue Coat proxy server. I am getting an error saying “The Duo authentication server returned an unexpected response” and the Duo.log shows a HTTP 407 error “Proxy authentication required…” error.

Our proxy server uses the signed on user’s credential to authenticate and it does not appear that Duo is able to pass the user information onto the server. Can this be true? If so, is there a way to make it work?

Thanks in advance.


You are correct, Duo for Windows Logon can’t provide authentication to the HTTP proxy while making the outbound HTTP request.