Every time I edit a modpack, it makes it so that my friend times out whenever he joins

[granite pecan]

your friend NEEDS to have the same mods you have no matter what, if you add one more they also need to add that same one to their instance. if you update a mod they ALSO need to update it. this is not the same for Client sided mods, hence why they're called "client sided" @wintry crown

[wintry crown]

Alright thank you

Well, he does have the same mods as me always