Cant play multiplayer despite having wargames

I cannot access multiplayer, despite having shelled out £17 for the war games map packs.

It says I need to download content, but I have already done this.

Help please!

Hi, Robacidgreen. At a minimum, you need at least an 8GB USB Flash Drive or an Xbox 360 Hard Drive to play Multiplayer mode in Halo 4. Do you have one of those?