when running on a network this means you are behind a router and modem
some modems and routers are missing a simple function called local loopback which means you can Not listen to yourself when using your real ip adress.
provide a link please with your real ip adress ( www.whatismyip.com
) and we'll see for you if you are up and running.
remember than in case of a router you need to forward ports.
( see top sticky called NAK ERROR)