I think you have to try forums about setup and feeding of that server. It's usually specific to your server and I will only offer one idea.
Many of the new routers have firewalls that block server use. As the server owner, you would have punched holes in the firewall or just turned it off.
New to cnet, was wondering if I could get any help:
Trying to play online with a friend as well as Skype him, but he is unable to connect to my server and I can hear him but he can't hear me on Skype. We can connect to other friends perfectly but not eachother for whatever reason. Problem persists while trying to Skype using cellphones as well as we have pin pointed it as an Internet problem. We both have the same Internet provider mine running at 35 mbps down and 5.5 Mbps up. His running at 50 Mbps down and 5.5 up. Any help would be great, already contacted Shaw (internet provider) and they can't even figure it out... This problem only seemed to start happening about 2 months ago before that everything was good and we can't find any obvious changes concerning the problem.
My comp: Windows 7, Toshiba
Router: Has 2.4Gz and 5Gz options but neither seem to work at the same time. Ethernet always works.

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