Stucks when i try to join error and then ban

Hello..

Sometimes when i join crossfire.. i type my ID and Password and going to join a server (UK 4)
when it's going to load the server and let me join, it stuck.. even if i wait.. it stays like this..
so i open task manager and close crossfire and re-open it..
when i type my ID and Password it says that i've been blocked from the servers for 5 minutes..
and when 5 minutes pass i can normally join..

can someone explain me what happens and if i can solve this problem?!