XF 2.1 Expected response code 250 but got code "452"

[sbj]

I am getting these kind of errors lately, what does it mean?

Server error log

    Swift_TransportException: Email to XXX@hotmail.com failed: Expected response code 250 but got code "452", with message "452 4.3.1 Temporary System Error " src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php:383

    Generated by: Unknown account 8 April 2020 at 22:09

Stack trace

#0 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(281): Swift_Transport_AbstractSmtpTransport->_assertResponseCode('452 4.3.1 Tempo...', Array)
#1 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(270): Swift_Transport_AbstractSmtpTransport->executeCommand('
.
', Array, Array)
#2 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(333): Swift_Transport_EsmtpTransport->executeCommand('
.
', Array)
#3 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(428): Swift_Transport_AbstractSmtpTransport->_streamMessage(Object(Swift_Message))
#4 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(444): Swift_Transport_AbstractSmtpTransport->_doMailTransaction(Object(Swift_Message), 'xxx@xxx...', Array, Array)
#5 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(176): Swift_Transport_AbstractSmtpTransport->_sendTo(Object(Swift_Message), 'xxxo@xxx...', Array, Array)
#6 src/XF/Mail/Mailer.php(292): Swift_Transport_AbstractSmtpTransport->send(Object(Swift_Message), Array)
#7 src/XF/Mail/Queue.php(138): XF\Mail\Mailer->send(Object(Swift_Message), Object(Swift_SmtpTransport), Array)
#8 src/XF/Job/MailQueue.php(12): XF\Mail\Queue->run(G)
#9 src/XF/Job/Manager.php(253): XF\Job\MailQueue->run(G)
#10 src/XF/Job/Manager.php(195): XF\Job\Manager->runJobInternal(Array, G)
#11 src/XF/Job/Manager.php(79): XF\Job\Manager->runJobEntry(Array, G)
#12 job.php(42): XF\Job\Manager->runQueue(false, 8)
#13 {main}

Request state

array(4) {
  ["url"] => string(8) "/job.php"
  ["referrer"] => string(62) "https://XXX.com/conversations/XXXX.34/page-4"
  ["_GET"] => array(0) {
  }
  ["_POST"] => array(0) {
  }
}

 

[Mike]

It's the response from your SMTP server, which is specifically:

452 4.3.1 Temporary System Error

So it's something going wrong on their end. You may need to contact your SMTP provider to understand what's happening.

 

[sbj]

Thank you, this is all I need to know. Will contact them about that.