Cannot join game.

Every time i try to join a a game, the loading screen with the loading bar at the bottom comes up as usual, but the problem is that the bar never complete, it moves steadily up to 9/10 of the whole bar , then freezes.
i've tried waiting patiently, but it only gets me back to the main lobby.
i tried restarting the pc, redownloading game, making new account, buying new items, trying out different maps, but the results are still the same.
plz help asap