Here is a step-by-step guide on how to configure the transparent SSO (Single Sign-On) Kerberos domain user authentication on the IIS website running Windows Server 2012 R2.
Start IIS Manager on your Web server, select the necessary website and go to the Authentication section. As you can see, only Anonymous Authentication is enabled by default. Disable it and enable Windows Authentication (First of all IIS always tries to perform anonymous authentication).