RTB has one grand server that runs and controls all other servers of RTB. This is called the Master Server. This is basically the heart of RTB. In order to run a normal Server in RTB, the game must connect to the Master Server, and recieve the message. The game scripts automatically do this for you, but the most common reason of not being able to start servers is that your firewall, or computer blocks your internet access to the Master Server. This can be solved by turning off all firewall, or by Port Forwarding.