Do you get a black screen if you try joining an existing save? The problem I mentioned above only happens between character creation and loading in to the game for the first time. In that case, if someone ran 2 instances of the game and created your character for you, it could let you join once they got into the game after character creation. If this is happening after getting into the game, that will not help, though.
Unfortunately, this may indeed be a network issue between you and your friends.
Are you shutting down all non-essential programs before starting the game, especially anti-virus and anything network related (utility or monitoring programs, etc)?
Have you checked your firewall settings? Many routers have built in firewalls, which could block inbound connections from the game.
Have you tried hosting in a new game?
Have you tried joining anyone else?
Try going into Arena mode, create an arena, open the Connectivity menu and check the settings, then exit to the main menu and try joining in the lobby. Alternately, create a multiplayer game lobby, exit and try joining. That helped a couple of people who had an issue crashing when trying to join, at least, so maybe it will make a difference in this case.
I assume you tried joining using the lobby and invite functions if everyone is using the Steam version, or all GOG, as well as Direct Connection (with a Server ID or IP address)?
If you use Discord, that may also be an option.
Try resetting your network adapters:
- click Start (or Search in Win 10), type cmd into the search box, right click Command Prompt and select run as administrator.
- type the following command and hit Enter
netsh winsock reset
- when that is done, there should be a message 'Winsock reset completed successfully'
- type exit and hit Enter, then reboot your computer.
For more details, see:
https://iihelp.iinet.net.au/Resetting_Network_Adapter_(Winsock_Reset)
If that doesn't help, please email supportdos2@larian.com with a dxdiag report (WinKey-R, type in dxdiag and hit enter, then when it finishes loading click on the 'Save All Information...' button and save the report somewhere handy), preferably for yourself and the host, and a link to this topic.
Also check the respective systems in the '..\SteamApps\common\Divinity Original Sin 2\DefEd\bin' folder for the gold.log and network.log files to include.
It may help if you rename the current network.log file, start the game and try joining one of your friends, quit, rename the file, restart and try hosting and finally quit, rename the file and try try the way you hosted that a friend can join, and play for a couple minutes until they get disconnected. Hopefully all of the network.log files it will help determine what the problem is.
