Errors you may see while maintaining iRedMail server

Postfix (SMTP)

Intended policy rejection, please try again later

Sample error message in Postfix log file:

Jul 24 06:43:08 mx0 postfix/smtpd[12719]: NOQUEUE: reject: RCPT from[xx.xx.xx.xx]: 451 4.7.1 Recipient address rejected: Intentional policy rejection, please try again later; 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.

Sender address rejected: not logged in

Sample error message in Postfix log file:

Jun 24 11:57:13 mx1 postfix/smtpd[2667]: NOQUEUE: reject: RCPT from[]: 553 5.7.1 <>: Sender address rejected: not logged in; from=<> to=<> proto=ESMTP helo=<>

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.

Helo command rejected: need fully-qualified hostname

Sample error message in Postfix log file:

Sep 22 08:51:03 mail postfix/smtpd[22067]: NOQUEUE: reject: RCPT from[]: 504 5.5.2 <EHSGmbHLUCASPC>: Helo command rejected: need fully-qualified hostname; proto=ESMTP helo=<EHSGmbHLUCASPC>

According to RFC document, HELO identity must be a FQDN (fully-qualified hostname). Sender sends EHSGmbHLUCASPC as HELO hostname, but it's not a FQDN. It's sender's fault, not your mistake.

As a temporary solution, you can whitelist this HELO hostname by adding a line like below at the top of file /etc/postfix/helo_access.pcre (Linux/OpenBSD) or /usr/local/etc/postfix/helo_access.pcre:


Sender address rejected: not owned by user

This error is caused by restriction rule reject_sender_login_mismatch in Postfix parameter smtpd_recipient_restrictions, in file /etc/postfix/

smtpd_recipient_restrictions =

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.


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/, then enable it in iRedAPD config file /opt/iredapd/ (plugins =), restart iRedAPD service. That's all.

Recipient address rejected: SMTP AUTH is required for users under this sender domain

With old iRedAPD releases, the error messages may be one of below:

SMTP AUTH is required, or it is a spam with forged sender domain

Recipient address rejected: Policy rejection not logged in

Sender domain is hosted locally on your iRedMail server, but sender doesn't perform SMTP AUTH to send email.


Recipient address rejected: Sender is not same as SMTP authenticate username

case #1

If the smtp authenticate username is different than the address in mail header From: field, you will get this rejection (by iRedAPD).



Notes: is the email address you used for smtp authentication.

case #2

If you're a member of mailing list or mail alias, and trying to send email with the email address of mailing list/alias as sender address, you will get same error. There's another setting you can try (either one is ok):


It will allow all members of mailing list/alias to send email with the email of mailing list/alias as the sender address.

unreasonable virtual_alias_maps map expansion size for

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 -- 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/

virtual_alias_expansion_limit = 1500

Reference: Postfix Configuration Parameters

Helo command rejected: ACCESS DENIED. Your email was rejected because the sending mail server does not identify itself correctly (.local)

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:

  1. Temporarily remove this HELO check rule on YOUR server, in file /etc/postfix/helo_access.pcre (Linux/OpenBSD) or /usr/local/etc/postfix/helo_access.pcre (FreeBSD), then reload Postfix service.
  2. Ask sender server system administrator to correct their HELO identity, they will experience same issue while sending email to others.

warning: do not list domain in BOTH mydestination and virtual_mailbox_domains

Sample log in Postfix log file:

Feb 20 03:31:54 mail postfix/trivial-rewrite[2216]: warning: do not list domain in BOTH mydestination and virtual_mailbox_domains

This error message means mail domain name is:

To solve this, please either use a different myhostname or don't use this domain name as mail domain (remove it with iRedAdmin). To use a different value for Postfix parameter myhostname, you must also change server hostname.

Dovecot (IMAP / POP3)

Plaintext authentication not allowed without SSL/TLS

Error message in Dovecot log file:

[ALERT] Plaintext authentication not allowed without SSL/TLS, but your client did it anyway. If anyone was listening, the password was exposed.

Dovecot is configured to force clients to use secure IMAP/POP3 connections, but your client is trying to use plain and insecure connection without TLS or SSL.

The BEST solution is updating IMAP/POP3 settings in the mail client application (e.g. Outlook, Thunderbird) to enable secure connection. Please check this link to see network port numbers and secure connection types.

The NOT RECOMMENDED solution is updating Dovecot config file to allow insecure connection, this is dangerous because your password is sent in plain text, if someone can trace the network traffic with network gateway / firewall, your password is explosed. if you clearly understand the risk and still want to enable insecure connections, please check this document.


connect to[]:10024: Connection refused

This error means Amavisd service is not running, please try to start it first.

After restarted amavisd service, please check its log file to make sure it's running.