So my friend recently got MCC on Steam because it was on sale, and I have had it since its release last year (December 2019). He wanted to start with Halo CE, so we played through it on Legendary. We had no problems whatsoever throughout our whole playthrough of Halo CE. So, naturally, we move on to Halo 2, playing in order of when the games came out, all on Legendary difficulty. We played Cairo Station fine, no problem. Then we get to Outskirts. We load the first time, but there was a bug where one of us alt-tabs and it crashes the game. Technically, the game is still running and you can hear it playing, but the person who tabbed out cannot tab back in. This forced us to restart, and since then, we have not been able to play Outskirts without disconnecting in co-op. So, we decide to move on, play through Metropolis fine, no problem. Same with the level after that, and with Oracle. We did encounter the bug before the Boss fight that many reported, where the cutscene before the fight disconnects us, but we decided to just skip the fight. So, we move on to Delta Halo. Same problem as Outskirts. Works the first time, one of us accidentally alt-tabs, never works again. Try to skip it to Regret, doesn’t work. We have sufficient hardware to play the games well, as we both have 16GB of RAM, plenty of SSD space (on our default internal SSDs), I have an i7-9700f and GTX 1660 Super, he has an i7 as well (idk the exact type) and an RTX 2070 (super, I think, but idk).
TLDR: Multiple levels in Halo 2 MCC has cause problems for my friend and I for co-op, where one of us gets disconnected from the host after the cutscene before the game loads. I am aware that others have experienced these problems, but we have experienced all of them, rather than one of them individually. We are able to play single player just fine, and as said before, we played Halo CE Co-op just fine.
We have tried pretty much any fix we could think of or find, listed as follows:
Skipping the cutscene to load the level directly
Swapping host
Checking internet connection
Reinstalling Halo 2 (including deleting the halo2 file from steamapps/common/mcc)
Verifying game cache
Launching with anti-cheat disabled
Pre-loading the level by each playing the first sequence in singleplayer, then switching to co-op
Checking NAT connection and type
None of these listed solutions (some of which worked for others) worked for us. This is extremely frustrating, as we want to be able to play every one of the halo games on Legendary, but apparently, for many, Halo 2 has problems. I have come here to see if there were any solutions someone had that I could not find or didn’t think of. Ideally, just getting the Halo 2 levels to load so we can play co-op is enough. The Oracle boss fight is not our priority. Additionally, I refuse to use Hamachi to launch a LAN connection, as I have seen others do, as I have gotten viruses through Hamachi on my older laptop (not the PC I am currently using)