1.6 KiB
Allow insecure POP3/IMAP/SMTP connections without STARTTLS
[TOC]
With default iRedMail setting, all clients are forced to use POP3/IMAP/SMTP services over STARTTLS for secure connections. If your mail clients try to access mailbox via protocol POP3/IMAP without TLS support, you will get error message like below:
Plaintext authentication disallowed on non-secure (SSL/TLS) connections
This tutorial describes how to allow insecure connection for daily use.
!!! note
If you just have 1 or few network devices like printer, firewall need to
send email with insecure connection, please follow this tutorial instead:
[Allow internal network devices to send email with insecure connection](./additional.smtp.port.html).
Allow insecure POP3/IMAP connections
If you want to enable POP3/IMAP services without STARTTLS for some reason
(again, not recommended), please update below two parameters in Dovecot config
file /etc/dovecot/dovecot.conf and restart Dovecot service:
- on Linux and OpenBSD, it's
/etc/dovecot/dovecot.conf - on FreeBSD, it's
/usr/local/etc/dovecot/dovecot.conf
disable_plaintext_auth=no
ssl=yes
Again, it's strongly recommended to use only POP3S/IMAPS for better security.
Default and recommended setting configured by iRedMail is:
disable_plaintext_auth=yes
ssl=required
Allow insecure SMTP connection on port 25
Please comment out lines below in Postfix config file /etc/postfix/main.cf
and reload or restart Postfix service:
smtpd_sasl_auth_enable = yes
smtpd_sasl_security_options = noanonymous
# force all clients to use secure connection through port 25
#smtpd_tls_auth_only=yes