More info about the error making MP unplayable.

So, there is this fastfile error that happens when you are about to load in to a match. Activision has gotten many support requests and people have told them about it, its been what, like 3 or 4 years since its been unplayable. What activision has said (according to some people) is that its a error on the players side. What clearly is not the case. Whats the point of even keepping the servers of the game up when you cant use them expect in zombies.