I've been getting this error modifying session message when i try and search for games with a party, It has only started happening over the past 3 days and it is extremly annoying because now i don't get averaging 5-6 games per hour, i average about 2 because i cant stayed in a lobby for more then 1 game, and thats if i even get into a lobby in the first place. I'm getting into a lobby about 1 in every 50 times i try searching it is very time consuming and annoying having to search so many times for nothing.
Same problem here (XBox), but I'm not even in a party.
Other threads reporting this problem too.
Hopefully Treyarch/Activision will pick up on this soon.
We've been having the sam problem the past 2 days. You would think that Treyarch would at least acknowledge that they were aware of the issuse.