For those afraid of misconfiguring/running their own server, you can use a ready to use docker with everything in it and with nice security defaults (no relay,

For those afraid of misconfiguring/running their own server, you can use a ready to use docker with everything in it and with nice security defaults (no relay, for instance): https://github.com/docker-mailserver/docker-mailserver https://github.com/docker-mailserver/docker-mailserver