Plesk Mail Servers Non Responsive

[Byron R]

Hello, I am currently experiencing and issue with my server.

It is running centOS 5.3 with Plesk 10.4.4 LATEST micro updates(prior to the incident), as of Thursday the 23rd of January all mail service (sending and receiving) have failed throughout the entire server.

When sending email from any domain name e-mail address on the server the following message is returned:

Message rejected by SMTP server. Check message content and attachments\nServer Responded: SMTP Server rejected email. Returned:451 qq temporary problem (#4.3.0)

The server bounces a message to the sender of an e-mail which is as follows:

This is an automatically generated Delivery Status Notification.

THIS IS A WARNING MESSAGE ONLY.

YOU DO NOT NEED TO RESEND YOUR MESSAGE.

Delivery to the following recipients has been delayed.

I have attempted service restarts for httpd, qmail, mysqld and crond. I have also made sure that ports 25, 110, 143 are all set to ACCEPT on the server. I have also upped the ulimit from 1024 to 2048.

I have rebooted the server also just to clear the e-mail queues and to ensure that there where no issues.

 

[IgorG]

Try to set correct permission with

# chmod 2511 /var/qmail/bin/qmail-queue

Also you can try to switch from Qmail MTA to Postfix and back.