Installing the libdvdcss on linux

Hi
I am trying to install the libdvdcss on Linux without any good result can someone help? I always have this error "the source
seem encrypted and can't be read are you trying to play a DVD without libdvdcss". I need you to show me how to install and maintain without having this message because i tried many times.
Thanks you very much

Error:
An error occurred
The source seems encrypted, and can't be read. Are you trying to play an encrypted DVD without libdvdcss?
