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# Allow insecure POP3/IMAP/SMTP connections without STARTTLS

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.

## 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