NuGet VS 2012 ServicePointManager does not support proxies with the https scheme

Question

I have recently upgraded from VS2012 RC to RTM, and since the upgrade to RTM, I can no longer access nuget. I receive the following error in the Manage NuGet Packages window.

Answer 1

A very late answer, but I've been getting the exact same message when restoring Nuget packages in VS 2015. It seems that last time I restarted my machine I didn't stop Fiddler, and Fiddler seems to have left something in a funny state. When I started and exited from Fiddler the issue went away.