Move detected spam to Junk folder

To move detected spam to user's Junk folder, you need to enable global sieve script in Dovecot.

You can find sample sieve rule file /var/vmail/sieve/dovecot.sieve.sample if you chose /var/vmail to store mailboxes during iRedMail installation. If you have a custom mailbox storage directory, the sample sieve rule file should be sieve/dovecot.sieve.sample under that directory. If you cannot find it, you can still download one from iRedMail project: here.

This file must be owned by user vmail and group vmail, permission 0500.

Now open Dovecot config file /etc/dovecot/dovecot.conf (on Linux/OpenBSD) or /usr/local/etc/dovecot/dovecot.conf (FreeBSD), make sure you have setting like below:

# Part of file: /etc/dovecot/dovecot.conf

plugin {
    sieve_before = /var/vmail/sieve/dovecot.sieve

Restart Dovecot service to enable it.

Note: we don't use sieve_default = for global sieve script, because it will be ignored if users have their own personal sieve rule files.