I was trying to diagnose some issues with ASP.NET Web Forms post backs so I turned off IPv6 even though none of my websites were bound to IPv6 addresses. I unchecked it on the adapter property page. I had no logical reason for doing this. Then Windows Update stopped working. This was from a Rackspace Cloud Server. I cannot imagine what kind of tunneling is taking place in various parts of the internet with IPv6 getting rolled out (finally).
Oh and by the way, I had trouble uploading this picture with BlogEngine.NET and I saw this article:
I did what the user said (in settings unchecked optimize which minifies) and it solved the problem, however I am on IIS 8 not IIS Express.
Videos of the Blow Hole: