SMTP Error: 454 4.7.1

Need Help
1

Hi,
could someone please help out?
My cake 4.5.3 application is delivering mails.
Some addresses are processed but some are not delivered and I have no glew why.
In the error-log I see a SmtpTransport problem.
The function _smtpSend in SmtpTransport.php is a bit complicated, I’m not sure what it is checking.

2025-07-11 13:51:24 error: Number Receivers:1
2025-07-11 13:51:24 error: Number Receivers:1
2025-07-11 13:51:24 error: Mail-to: a correct mail address
2025-07-11 13:51:28 error: [Cake\Network\Exception\SocketException] SMTP Error: 454 4.7.1 <a correct mailaddress>: Relay access denied in /var/www/web489/html/latotal/vendor/cakephp/cakephp/src/Mailer/Transport/SmtpTransport.php on line 632
Stack Trace:

  • /var/www/web489/html/latotal/vendor/cakephp/cakephp/src/Mailer/Transport/SmtpTransport.php:532
  • /var/www/web489/html/latotal/vendor/cakephp/cakephp/src/Mailer/Transport/SmtpTransport.php:206
  • /var/www/web489/html/latotal/vendor/cakephp/cakephp/src/Mailer/Mailer.php:407
  • /var/www/web489/html/latotal/src/Controller/Component/controllerComponent.php:228
  • /var/www/web489/html/latotal/src/Controller/RepairsController.php:605
  • /var/www/web489/html/latotal/src/Controller/RepairsController.php:770
2

This is probably not a code issue on your part, but something about the configuration of the mail server you’re connecting to. Perhaps direct settings, or things like SPF or DKIM.

3

if you google that you will find many places where it explains what is going on.

This is NOT a CakePHP issue.

4

Hi all,
I have made tests with different MailTransport - Configs. It is now working, but I don’t know the reason. Maybe the used mail-box owner has restrictions. The provider support went not into the depth, or I had to pay. Anyhow thanks for confirming, it’s not a cake problem.