NAT STATUS: Strict

[MightyPotato]

I recently bought this game along with three others (my brother and two friends). Since me and my brother are on the same network and we both have NAT Status set to strict, we can play co-op mode together but our friends have their NAT Status set to moderate and we can't play with them. I tried everything. Tried different ways of port forwarding and nothing worked. Does anyone have a solution?

[iTz-Funny]

You are with (STRICT NAT) which means that you have a probability of finding matches in lower MP than someone with OPEN/MODERATE NAT, STRICT NAT means that you cannot be the hostile in any match (leader), So do the following, connect all of you in the normal online campaign mode, within the game, set it to search for an online match, wait a bit and return to the game's lobby, (nat will remain strict) with the 3 of you in the lobby, ask your friend to invite you for the match, if not, everyone enter the normal campaign, and within the campaign mode, your friend (with nat open/moderated) invites you to his session, that's how it works here. FROM BRAZIL

[Ubi-Vinci]

Hello, MightyPotato

Strict NAT may often be caused by high security / firewall settings in your router.
If you know how to do it, check your router config and lower the firewall one step.
As explained above by iTz-Funny, you will have issues with co-op with strict NAT.

Ubisoft Support