Multiplayer not working

[AdamN]

First of all, you need to mention what games are having problem, and also what kind of internet all the players involved are using (ie. are they behind NAT/shared internet connection? can they successfully opened the port?) if you're trying to play over the internet without VPN, also have you tried using VPN?

Are any of the players seeing a red/orange message on screen?

Most of the issue in adhoc multiplayer are related to firewall, restricted ports (< 1024), port forwarding, or very high latency (> 200 ms)

PS: AFAIK the only working public adhoc server are socom.cc and psp.gameplayer.club, but if you're playing on LAN you need to select the correct IP (don't use localhost)