I just got my game like 10 days ago on PS3, and I have never been able to play or join co-op at all.
When I try to join either my friend's game or a random co-op game, I always get stuck on "joining game" and sometimes it ends with an error message "can't connect".
This also happens with some of my friends whether they join my co-op or a random co-op game.
I can still play Battles of Kyrat, Map Editor and Map Browser but I never get to join a co-op game or have friends join my game through invites.
I sent Ubisoft an email, and all what they said is just that I have to forward some ports which I've already forwarded, but still no new result.
So I posted my question here maybe one of you guys faced this problem and was able to fix it somehow.
Thanks in advance!