Canon EOS 60D error 20

hello wih regards
i have a canon 60d and recently i receive this message: 
"error 20 shouting is not possible reseat the battery or turn off and on"
but turning on and off not solved the problem.
i very pleased if any one can help me.
i have olso changed the lens but no effect and mirrors are in right positions sometimes curtain in front of ccp remain open 
i think it is from shouter.