Mail is not delivered to mailboxes on the server and there is unusual greeting while connecting to port 25 Plesk server using telnet
Port 25 is listened by
sendmail service or some other process.
Try to connect to the server (
<server-ip>should be replaced with server IP address):
$ telnet <server-ip> 25 Trying <server-ip>... Connected to server.hostname.com (<server-ip>). Escape character is '^]'. 220 domain.tld ESMTP`
The output may be different if Postfix is used:
$ telnet <server-ip> 25 Trying <server-ip>... Connected to server.hostname.com (<server-ip>). Escape character is '^]'. 220 domain.tld ESMTP Postfix`
There is server hostname should be reported instead of
server.hostname.comin the SMTP greeting (Qmail takes it from the
/var/qmail/control/mefile). If there is another (non-Qmail) greeting, it means that the SMTP port is listened to by another software and that the Plesk SMTP service is not working because of this.
The process that is listening on the 25 port can be found as follows
# /usr/sbin/lsof -i | grep -i smtp command.
If this process is
xinetd, check if any SMTP service is configured other than
psa_smtp. This can be determined using
# grep smtp /etc/xinetd.d/*
If port 25 is listened to by
sendmailor some other process (other than
postfix), such service should be stopped and removed from autostart.
Check mail server configuration files:
#111283 Plesk for Linux services logs and configuration files
If you receive one of the following errors, visit:
connection timeout connection refused
#1388 Can not send an e-mail to Plesk mail server: "connection timeout" or "connection refused"
#125894 Unable to receive/send e-mails