Intranet Windows Authentication returns nothing.

I have..
<authentication mode="Windows" /> ...in my web config, and when I try to display the username on the form I get nothing.  I guarantee that no one, least of all me is on the corporate network not being logged in.  I also need to access active directory to find a couple of roles to grant access to certain forms.
I have done this dozens of times using Forms authentication, but these methods just whine about providers not being set up if you try it with Windows authentication.
I am using Visual Studio 2012 and IIS Express.