[Sarepean]

Edited:


If your DMZ is set up correctly and your port forwarding is set up correctly (one or the other should be set up and preferably not both), then it shouldn't be your router causing it which means that the error is either in your client version (which it can't be since you can connect when it's localhost) or in your files (which is unlikely since localhost works). Don't use the "no-ip.org" approach, go to whatismyip.com and use the IP they give you there as your external and use your network internal IP address.