So, how is it going? i tried to enter many halo 4 games, but i'm getting same error as you, or even others...
Another thing to note, is that when i go online on my halo, it changes my tag to 0000 and doesn't allow me to change it while i'm online. I have googled a little, and saw that when this 0000 tag thing occurs it is some protection from 343 industries on the game that kinda ban you.... Happened to anybody else? how would you solve it? Is that what is helding me from being able to join games even when it says people games are joinable?
Edit: Managed to play BOPS II Multiplayer on wi-fi, but halo 4 still doing 0000 tag and say my game is not joinable, while others are joinable and when i try to go to them, the game simply does not connect =/
