cant play rank games

When i try to start a rank game. The client just loads and cant enter the rank game lobby. Then several seconds late, I go back to the main page of client. And I use some of my friends accounts to start rank games. It works. No any problems, It just starts as general. Eventhough, I ask my friends to invite me to the rank game lobby they creat, i cant join it neither. I want to search some information about this issue online, but nothing is found. Plz tell me what is worng, and gives me any help about it. Thanks very much.