"Unable to join party" error

[USweapon]

i just got halo 2 to work for my space PC that has vista on it (my main uses XP) and i made a LIVE account with silver membership. however when i look for a game, theres only like 30-40 games. is that normal? also i cant join ANY server cause i get "Unable to join party. Try again later" or something like that. anyone how whats wrong?