Sometimes with Windows Server 2012, you may not be able to login on a fresh server, even those RDP rules, and access has been allowed. You will need to check the RDP port is open in Windows Firewall.
To open the port
* Open Windows Firewall
* Click Inbound Rules
* Add New Rule
* Type RDP Port (should be 3389) unless you have changed it in the registry
* All on all profiles, domain, public & private.
Thats all