On an iRedMail, when receiving an email from steam, the mail server rejects the email with the error message “Recipient address rejected: Intentional policy rejection, please try again later”.
Jan 31 20:31:46 mail postfix/smtpd[2042109]: Anonymous TLS connection established from smtp-03-tuk1.steampowered.com[208.64.202.39]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits) Jan 31 20:31:47 mail postfix/smtpd[2042109]: NOQUEUE: reject: RCPT from smtp-03-tuk1.steampowered.com[208.64.202.39]: 451 4.7.1 : Recipient address rejected: Intentional policy rejection, please try again later; from= to= proto=ESMTP helo= Jan 31 20:31:47 mail postfix/smtpd[2042109]: disconnect from smtp-03-tuk1.steampowered.com[208.64.202.39] ehlo=2 starttls=1 mail=1 rcpt=0/1 data=0/1 quit=1 commands=5/7
This is due to gray listing in iRedMail server.
To whitelist steam in iRedMail, run
/opt/iredapd/tools/greylisting_admin.py --disable --from '@steampowered.com'
Example
root@mail:/var/log# /opt/iredapd/tools/greylisting_admin.py --disable --from '@steampowered.com' * Disable greylisting: @steampowered.com -> @. root@mail:/var/log#
