- Plesk 12.5 for Linux
- Plesk 10.x for Linux
- Plesk Onyx for Linux
- Plesk 11.x for Linux
- Plesk 12.0 for Linux
- Plesk 12.5 for Windows
Email is not delivered. The following messages are shown in the
CONFIG_TEXT: handlers_stderr: DEFER
DEFER during call 'grey' handler
milter-reject: DATA from mail.example.com[x.x.x.58]: 451 4.7.1 Service unavailable - try again later; from=<[email protected]> to=<[email protected]> proto=ESMTP helo=<email.example.com>
CONFIG_TEXT: greylisting filter: Starting greylisting filter...
/usr/lib64/plesk-9.0/psa-pc-remote: handlers_stderr: REJECT
/usr/lib64/plesk-9.0/psa-pc-remote: REJECT during call 'grey' handler
/usr/lib64/plesk-9.0/psa-pc-remote: Message aborted.
postfix/smtpd: reply: SMFIR_REJECT data 0 bytes
postfix/smtpd: E612613C0057: milter-reject: DATA from unknown[203.0.113.2]: 550 5.7.1 Command rejected; from=<[email protected]> to=<[email protected]> proto=ESMTP helo=<DD2HMALPPPPT02.hmail.sg>
After a while, email finally arrives into the mailbox with the following entries in
CONFIG_TEXT: Starting greylisting filter...
SKIP during call 'grey' handler
This is an expected behavior of Greylisting that introduces a short delay before accepting mail: mail gets deferred for the first time, then gets delivered for the second attempt to send an email. In most cases, mail from a valid sender will be delivered within an hour, but depending on how the sending server is configured, it could be much longer.
Mail from a spammer, on the other hand, will be deferred for 1 time and mail sending will not be retried: spammers usually send mail in bulk to thousands of recipients and do not bother with resending. See Plesk Administrator Guide for more details.
Delay takes place because Greylisting verifies three components of the message: IP, sender, recipient. Based on these components Greylisting determines whether it should issue a temporary reject code or accept the message.
As a workaround, to prevent delay, put required mailbox or the whole domain
into White List in:
Tools and Settings > Spam Filter > White List
This way email from the white-listed senders will be accepted without passing through the greylisting check as well as trough SpamAssassin.
Alternatively, disable Greylisting spam protection on the whole server:
Tools and Settings > Spam Filter > Switch on server-wide greylisting spam protection
The following statuses can be seen in
: DEFER, SKIP, REJECT
In terms of Greylisting
means 'try again later';
means 'allow delivery';
means that the sender IP is blacklisted globally.