Okay here's the thing. I log in to my laptop and open up Halo Ce, And I look in multiplayer, Internet, At all the Servers. However nothing comes up! It's just blank, So decided to open up my server and see what happened. I had no one joining and that's a new thing on my server I Turned off firewall and added ports to firewall but to no avail. I tried other games like FunOrbs Dungeon Assault and I clicked on dungeons and raids, To find no dungeons raidable! Nothing came up just like in Halo. I then tried Minecraft and I don't seem to be able to connect to any of the servers i have, The connection doesn't exist!
First of all check your router, and the setting on the hardware firewall that it may contain.
Set it to low if you can,flood protection should be turned off if the option exists. Then test to see if the server list is generated in the game.
Make sure you are not running a software firewall at the same time on the pc its self.
Only use one firewall, hardware or a software one.
As said port forward the ports used for the game making sure you use both protocols TCP, UDP, to open port ranges.
Check that UDP is enabled in the router.