title: What sets User.Identity.IsAuthenticated in an ASP.NET MVC app?
body: <p>I'm using the Facebook C# SDK, and I authenticate the user by their Facebook account. Once I've performed all the checks to "authenticate" them, I call <code>FormsAuthentication.SetAuthCookie(email, false);</code></p>
  
  <p>Does performing that call allow me to have access to <code>User.Identity.IsAuthenticated</code> within my actions? What about if I didn't make that call?</p>
  
  <p>I have some actions that will return different views based on their authentication status, and want to make sure <code>User.Identity.IsAuthenticated</code> is reliable in an MVC 4 app.</p>