I have created an MVC 5 application (following the Create an ASP.NET MVC 5 App with Facebook and Google OAuth2 and OpenID Sign-on tutorial) and uncommented the line:
app.UseGoogleAuthentication();
Everything works fine. I can login using Google. I then change the project properties to host the application under my local IIS server (instead of the default IIS Express). The Google login no longer works. The line:
var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();
in ExternalLoginCallback always returns a null, whereas under IIS Express loginInfo is populated. This means the browser is just bounced back to the Login page. I'm running on Windows 8.1.
I have seen other people having issues with null exceptions, I don't get any. I have restarted IIS. I have rebooted my machine and still I get the same result.