Unable to connect

[woodjoshua28]

Hello 

when I am trying to play Call of Duty with another person on the same network only the first person to load the game is able to connect to the server 

is there a solution to this 

[Cynric]

@woodjoshua28  On what kind of device are you playing CoD?

[woodjoshua28]

I am playing on PC aswell is the other person both connected using Ethernet 

[Cynric]

@woodjoshua28 I think that the association between the port number(s) could be the issue. For example CoD-Server sends to your router external IP address on port 12345 and the 1st PC is mapped to router internal address (often 192.168.1.1) port 12345 and thus ALL traffic of that protocol using port 12345 is only going to the 1st PC. 

IP6 is not a solution because VF doesn't supply it and I believe that CoD doesn't use it either.

If you can look into the port mapping on the router and see if the CoD port is mapped to a single IP address or to a range (e.g. 192.168.1.0/24)? Also is UPnP on or off, whichever it is currently at try the opposite.

[P1x3l8]

I'm having similar issues with COD but on PS4 Pro via ethernet... Difficulty joining lobbies and variation in lobby and in-game latency - anything from 23 to 58 and 15 to 27 respectively? With VM I joined games quickly and my average ping was 22. Even had some kicks and some rubber banding which I haven't ever seen before!

[Cynric]

@woodjoshua28  Additional: I have seen elsewhere that the default port number you have to open on the PC firewall is 28960. The suggestion that I read is that on the 2nd PC firewall open port 28961 and associate it with CoD.