[2020] Is there any way to fix the desync issues?

Hello pewp3wonline, thanks for posting about this in the forums.

Are you able to screenshot the message you get when you desynch from the game? Does it happen to you as the host or as your friend as the friend who joins the game?

What are you doing in the game when it de syncs? If the other player leaves the game completely, will the game continue or does it freeze?

Im sorry to hear that the troubleshooting did not work for you pewp3wonline.

Do you have any connectivity issues in other games or just this game when you try to play together? Do you both use the Ubisoft Connect game launcher to play?

Have you both also went as far as to set up your router for port forwarding by opening the ports on your router to -

UDP: 18000 for the Anno 1800 game

TCP: 80, 443, 13000, 13005, 13200, 14000, 14001, 14008 ports for the Ubisoft Connect launcher?

Hey pewp3wonline, as well as forwarding the ports and what you have already tried, there is a possibility of either you or your friend having double nat, but if this was the case it would affect most games you and your friend were trying to play together and as you have said this only seems to affect Anno 1800. There is also the possibility the save file may be corrupted.

Do you both play with mods and do you have many of the DLCs activated on your save?

My best advice would be to get in contact with us and make a support ticket. We will ask you what troubleshooting you have already done so please be specific, then we will ask you for a screen shot of your port forwarding settings. After that we can escalate this to our technical team to look at and advise. If no solution is then found, we know its either a problem with the game or a corrupted save file, so if you can I would also attach the save file to the case too.

You can make a new case here - https://support.ubisoft.com/en-GB/Cases/New

I would encourage you to do this as you've put so many hours into the game, it would be a shame to not be able to play this campaign with your friend.