title: Ports open, but no one can connect
body: <p>I am programming a server system for a small RPG game made with SFML. This is my first project since we switched our ISP to Comcast and I am having trouble with people connecting to the server. I can connect locally fine and all of the port checking tools say that the port is open, but my friends cannot connect using my external IP. I turned my firewall off on my router and on my computer to see if it'd help the situation at all, but the same thing is occurring. </p>
  
  <p>Comcast gave me an Arris TG862G-CT router.</p>
  
  <p>Here's an image of the port forwarding page:</p>
  
  <p><img src="https://i.stack.imgur.com/CXcUf.png" alt="enter image description here"></p>
  
  <p>The port is shown as open, but my client cannot connect:</p>
  
  <p><img src="https://i.stack.imgur.com/Phx3e.png" alt="enter image description here"></p>