Not Entering Server

  • I am trying to go inot a epoch server. I downloaded both epoch and dayz on the mods and have played in the past. Today i tried to senter a server, arma 2 loads up and a flash of the lobby appears with all the names on the right but i then get put back into the arma loading screen then to the main arma 2 menu. Can you help and how do i stop this.