# 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 ``` ## 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 Please comment out below line in Postfix config file `/etc/postfix/main.cf` and reload or restart Postfix service: ``` smtpd_tls_auth_only=yes ```