Had you tried this tutorial? https://www.digitalocean.com/community/articles/how-to-set-up-a-postfix-e-mail-server-with-dovecot https://www.digitalocean.com/co

Had you tried this tutorial? https://www.digitalocean.com/community/articles/how-to-set-up-a-postfix-e-mail-server-with-dovecot https://www.digitalocean.com/community/articles/how-to-set-u... I had used it to setup a test server and had no issues -- FYI, the date on the article is today, but the original article has been available for a few months so perhaps the article has been updated.