Ticket Notification

[hannibal_]

Hello All

For several days ticket notifications do not work.
I can send email, but when I change the queue agent does not receive the message.
I checked the configuration of the notification, everything seems to be ok.
I have no idea what could have happened.

Do you have any ideas what could have happened?

[crythias]

but when I change the queue agent does not receive the message.

If Agent=Person who made changes, Person who made changes won't receive notifications
Or, agent preferences, notifications "yes" and queues highlighted in My Queues.
Or, errors in otrs.log, etc., referencing sending problems.

[hannibal_]

This is error log:
Thu Nov 28 15:50:58 2013][Notice][Kernel::System::Ticket::Event::NotificationEvent::_SendNotification] Sent agent '<agent_name>' notification to '<email_addres>'.
[Thu Nov 28 16:57:10 2013][Error][Kernel::System::Email::SMTP::Send][163] Can't send message: 553Go ahead...
5.7.1 We don't relay mail
! Enable Net::SMTP debug for more info!
[Thu Nov 28 16:57:10 2013][Info][Kernel::System::Email::Send] Error sending message

[crythias]

Your SMTP server won't send mail for your notification sender / recipient combination.