Sample error message in Postfix log file:
Jul 24 06:43:08 mx0 postfix/smtpd[12719]: NOQUEUE: reject: RCPT from sender.com[xx.xx.xx.xx]: 451 4.7.1 recipient@my-domain.com: Recipient address rejected: Intentional policy rejection, please try again later; from=sender@sender-domain.com to=recipient@my-domain.com proto=SMTP helo=
This error is caused by greylisting service, sender server will retry to deliver the same email, and your server will accept it after few retries.
Sample error message in Postfix log file:
Jun 24 11:57:13 mx1 postfix/smtpd[2667]: NOQUEUE: reject: RCPT from mail.mydomain.com[1.2.3.4]: 553 5.7.1 <sombody@my-domain.com>: Sender address rejected: not logged in; from=<sombody@my-domain.com> to=<receipent@receipentdomain.com> proto=ESMTP helo=<client_helo.com>
This error is caused by incorrectly configured mail client application, not a server issue.
All mail users are forced to perform SMTP auth before sending email, so you must configure your mail client applications (Outlook, Thunderbird, ...) to enable SMTP authentication.
This error is caused by restriction rule reject_sender_login_mismatch
in
Postfix parameter smtpd_recipient_restrictions
, in file /etc/postfix/main.cf
:
smtpd_recipient_restrictions =
...
reject_sender_login_mismatch,
...
It will reject the request when $smtpd_sender_login_maps specifies an owner for the MAIL FROM address, but the client is not (SASL) logged in as that MAIL FROM address owner; or when the client is (SASL) logged in, but the client login name doesn't own the MAIL FROM address according to $smtpd_sender_login_maps. Check manual page of Postfix configuration file for more details.
Removing reject_sender_login_mismatch
and restarting Postfix service fixes
this issue.
Note
If you want to allow some users to send as other users, or allow all users
to send as their alias addresses, or allow member of mail list/alias to send
as mail list/alias, you should try iRedAPD plugin reject_sender_login_mismatch
instead (requires iRedAPD-1.4.4 or later releases).
Read comments in file /opt/iredapd/plugins/reject_sender_login_mismatch.py
,
then enable it in iRedAPD config file /opt/iredapd/settings.py
(plugins =
),
restart iRedAPD service. That's all.
Sample error message in Postfix log file:
Feb 11 19:59:06 mail postfix/cleanup[30575]: warning: 23C334232FB3: unreasonable virtual_alias_maps map expansion size for user@domain.com -- deferring delivery
It means the maximal number of addresses that virtual alias expansion produces from each original recipient exceeds hard limit, please either increase the hard limit (default is 1000), or reduce alias members.
To increase the limit to, for example, 1500, please add below setting in
Postfix config file /etc/postfix/main.cf
:
virtual_alias_expansion_limit = 1500
Reference: Postfix Configuration Parameters
It means sender mail server uses a FQDN hostname which ends with .local
as
HELO identity. .local
is not a valid top level domain name, and all mail
servers should use a valid domain name which is resolvable from DNS query.
Two solutions:
/etc/postfix/helo_access.pcre
(Linux/OpenBSD) or
/usr/local/etc/postfix/helo_access.pcre
(FreeBSD), then reload Postfix
service.This error means Amavisd service is not running, please try to start it first.
# service amavisd restart
# service amavis restart
# /etc/rc.d/amavisd restart
or # rcctl restart amavisd
After restarted amavisd service, please check its log file to make sure it's running.
Notes: