To send encrypted or digitally signed messages, you need to configure an encryption technology, either OpenPGP or S/MIME.
Akken ad tazneḍ iznan ittwawgelhen neɣ yettwazemlen s wudem umḍin, tesriḍ ad tsewleḍ tatiknulujit n awgelhen, OpenPGP neɣ S/MIME.