April 2016
I've played DS3 co-op until Chapter 4 with my friend. Everything went fine without a hitch, but the next day the game refused to connect to each other, regardless of who was hosting. We've tried so far:
-Defrag the game
-Repair the game
-Reinstal Origin
-Reinstall DS3
-Port Forwarding
-Inviting through game and though Origin overlay
This issue popped out of nowhere overnight. If we've never been able to connect to each other in the first place it would've been a different matter entirely, but we DID played together already, but now the game refuses to work...
April 2016
Having the same problem here in PC , we did played before and suddenly lost connection both of us and we never able to play together again