When sending mail to a mailbox, it gets bounced with a message saying that no such mailbox exists.
The mail is bounced back with one of the following errors:
Hi. This is the qmail-send program at SERVER. I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out
This address no longer accepts mail.
Sorry, no mailbox here by that name. (#5.1.1)
550 Requested action not taken: mailbox unavailable Givingup.
User not known Giving up.
Sorry your message to email@example.com cannot be delivered. This account has been disabled or discontinued.
Mail recipient mailbox does not exist.
- Check the MX record of the domain you are sending a message to:
nslookup -q=mx example.com
example.com MX preference = 10, mail exchanger = mail.example.com
mail.example.com internet address = 18.104.22.168
# dig -t mx +short example.com
# dig +short mail.example.com
1.1. If the MX record resolves into a different server, and this domain is not present on the Plesk server, ask administrator of the server if the mailbox exists.
If the error occurs while sending mail to the Plesk server, make sure that the mail address exists and that mail service for the domain is enabled.
Also, check that the MX (A) record of the destination domain resolves into appropriate server.
If the MX record resolves into a different server, but the domain is hosted on the Plesk server, correct the MX record in DNS settings of the domain. Disable mail in Plesk > Domains > example.com > Open in Control Panel > Mail tab > Settings
If DrWeb is installed on the server and it has no valid license, make sure that
LicenseLimitis set to "
# grep License /etc/drweb/drweb_qmail.conf
LicenseLimit = pass
Make sure that the recipient domain is not listed in the
/var/qmail/control/localsconfiguration file. This file must contain only "
Another possible reason for the problem is that two SMTP service processes are running on the server. An example for Windows (commands below executed in a commandline
TCP 0.0.0.0:25 0.0.0.0:0 LISTENING 1996
TCP 203.0.113.2:25 0.0.0.0:0 LISTENING 1524
tasklist | findstr "\\<1996 \\<1524"
MailService.exe 1524 Services 0 56,348 K
MESMTPC.exe 1996 Services 0 3,048 K
Check which one of SMTP servers is used by Plesk ( Tools&Settings > Services Management ) and stop the process of another one.
Reconfigure mail settings:
mchkutility rebuilds Qmail configuration files, restores missing mail account directories, etc., according to settings from Plesk database. Please note, that the utility may run for a long time and the mail accounts may not be accessible, while it runs.