One thing you must ALWAYS do is make sure your firewall is ALLOWING the port to be opened. It may ask you to Block/Unblock the program's features the first time you try to connect. If so, click UNblock. If not, go to Control Panel, and then go to firewall. Add an exception for the program to be able to make connections on the proper port (TCP). If that doesn't work, follow Razoron's advice and fully forward the port, step by step. If you have further trouble, Google your router and try some troubleshooting. You'll get it!