With Let's Encrypt you can generate a free SSL certificate for your whole server: SMTP, POP3, IMAP, FTP, the webserver(s) and DirectAdmin is covered by this. First, you need to have Let's Encrypt enabled. Secondly, this only works for the server hostname.

  1. Navigate to the directory:
    cd /usr/local/directadmin/scripts
  2. Request the certificate:
    sh letsencrypt request servername.yourwebhoster.eu
  3. Make sure that the following services are restarted, if installed:
    1. apache
    2. exim
    3. dovecot
    4. proftpd
    5. pureftpd
    6. nginx
  4. DirectAdmin will take care of regenerating the Let's Encrypt certificate.