about 5 years ago - AndrewT - Direct link
Does this happen whether you are host or not?

Are you opponents also Mac, or Windows, or mixed?

FYI here's my standard checklist for EU4 MP issues:


- make sure all players have opened the required Steam ports in all their active firewalls (each player may have up to 3)
https://support.steampowered.com/kb_article.php?ref=8571-GLVN-8711
- all players delete their documents/paradox/eu4/gfx/ folders, and let the game recreate them
- use no mods at all
- all players use the same language in-game
- when anyone gets an OOS error, re-host the game immediately, as it will almost certainly crash soon
- start your multiplayer games and wait half a minute or so before unpausing without any player performing any action at all. Only after the game has been unpaused should players begin doing actions like setting rivals, declaring war etc.