for me its always been just unsubscribe too the conflicting ones that are older. as for the reason why the add-ons stay restricted even turning off all of them but the back too school, that's something within your files. I would unsubscribe too any unused add-ons (if not all of them) and just download what you use directly. as a side note, there's always been a issue with online play with friends. have him try joining while you have it running by yourself (or vise-versa)


I am just some random gamer who has run into a similar issue. it was conflicting with another map I had. I ended up having to unsubscribe to the other map in order for it to allow me to play it

Bit late to this, but that is completely normal. You can ignore that conflict for any campaign that is split into multiple parts.

If you want some technical explanation though, read on:
Campaigns rely on a file called the "mission file", which tells the game what maps are part of it, in what order, which survivors to use, what the campaign's name is, where to apply unique models and textures, etc. - Each part needs to have this mission file.
However, the game isn't intelligent, so it just sees "All these different parts have this same file in common. WARNING, CONFLICT. WHICH ONE DO I USE?!".
The game doesn't know that all the parts are just individual chunks of a larger mod, it sees them all as seperate mods, so any files that are in common show up as conflicting.

All this means is "These seperate add-ons have a file that looks the same, and the game doesn't know which of those identical files to use".

The same thing can happen if a texture, model, or sound was accidentally duplicated between the different parts, but usually it's just the mission file, and it has zero effect on the gameplay.