how come in halo 3 when i go to matchmaking and i go to team slayer in...

[Johnny]

...ranked matches i cant play it? its there, but its like not shaded in so you cant go to it

 

[Josh O]

Have you downloaded the heroic maps and cold storage? i suggest that if you haven't and there free.
if not you might need to upgrade your account to gold membership if you have silver. play social in the mean time

 

[RageKage117]

do u have all the maps because if u dont it wont let u play

 

[Ark]

you need to download the heroic map pack and cold storage