We set up a Windows Media Server just like we’ve done many times before, but this time we were not able to connect to the streams from outside the local network.? After spending a lot of time verifying that it wasn’t a firewall problem, I found this article that gave an answer: the media server rejected the requests because it didn’t like the dns name in the URL.? Adding the public dns name to the localhost like of the media server’s hosts file fixed it.

Thanks, David!