
Even after all of this we have the same issue of only the host getting the completion. Reset modems, restarted pc's, restarted the game, uninstalled and reinstalled the game as well as halo 2 individually, verified game files (all were there), unplugged our keyboards, changed graphics settings, played through multiple missions, and we tried changing things I stated in my last paragraph. We've tried most if not all of the basic fixes for something like this.

Difficulty, skulls, classic or remastered graphics, or who hosts, none of it makes a difference. Whenever we complete a mission, whatever that mission may be, only the host gets the completion, and the non-host has the missions as "unplayed" when viewing missions, and the counter for missions completed in the stats menu doesn't go up. My friend and I came across a really annoying bug involving the halo 2 co-op campaign. So I'm gonna try to get help here as a last resort.

I've also tried searching for this issue online, but I could hardly find anything related and when I did it was a dead end with no fix.

So I tried asking 343 for help with this issue, and that was 3 days ago and the only reply I got was unhelpful as it asked me to do something that I stated I already tried.
