In Halo 3 live what does it mean when it says one or more players do not...

[Jason]

...have the maps necessary? what do they mean by that and how can i get the maps i need to play halo 3 on xbox live?

 

[br_romulo1493]

means that someone in your party does not have the maps from the market place which you buy with microsoft points, so you can't play those maps if they are in your party

 

[butters57]

it means that they dont have the map pack so you only go to the basic maps not the one you paid for