In Call of Duty 4, when some people invites me to a game, it wont let me invite?

I am playing xbox live in call of duty 4 and when my friends invites me to a match, it wouldn't let me invite and it says "can't connect to host" what should i do to fix this?
In Call of Duty 4, when some people invites me to a game, it wont let me invite?
it means the cod 4's servers r full that means to many people r online in match making activision never thought it wood be this big of a game soo..... yea they are fixing problem though idk how to fix it i just wait it out myself i get it badly somthimes
Reply:if their connection is bad it is either because of your internet or because of theirs...
Reply:maybe if you ask it nicely...
Reply:This happens when the party they are in "backs out", meaning the host closed the room. They invited you when it was open, but it was closed by the time you accepted it.