The recieved string is longer than maximum allowed (41 > 40)

After adding objective "lobby1" to scoreboard sidebar it kicked me out of the game and I'm no longer able to connect to the server. Internal Exception: io.netty.handler.codec.DecoderException: java.io.IOException: The recieved string is longer than maximum allowed (41 > 40)

Screenshot: http://imgur.com/LUk4a4S

Edit: Editing NBT data so that objective is no longer displayed allowed me to join game
Edit2: Don't mind the ! = in the command... I fixed it to = !