Your software
Mautic: 3.2.5, 3.3.1 and 3.3.2
PHP: 7.4
MySQL: 5.7
CentOS: 7.9
cPanel: 94.0.4
PHP-FPM: Activated
Service to send mail through: sendmail
SMTP encryption type: none
How should email be handled?: Send inmmediatly
Your problem
I have been using Mautic for several years now and it always worked fine, however, from version 3.2.5 to 3.3.1 as well as with 3.3.2, it is having problems to send the emails. I have tried all kind of combinations for SMTP or Sendmail and get different kind of errors for each one.
At this case, we are using sendmail and the problem is that, when we execute:
sudo -u [USER] /usr/local/bin/ea-php74 /home/[USER]/public_html/bin/console mautic:campaigns:trigger --batch-limit=10 > /home/[USER]/public_html/var/logs/log-campaigns-trigger.log
it continuously shows the following errors
[2021-03-24 17:18:33] mautic.ERROR: [MAIL ERROR] Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b746967425448715072@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) Log data: >> MAIL FROM:<envios+bounce_605b746967425448715072@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) !! Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b746967425448715072@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) (code: 0) (send); [EMAIL] {"exception":"[object] (Swift_TransportException(code: 0): Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b746967425448715072@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\nLog data:\n>> MAIL FROM:<envios+bounce_605b746967425448715072@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\n!! Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b746967425448715072@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0) (code: 0) at /home/[USER]/public_html/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Plugins/LoggerPlugin.php:124)"} []
[2021-03-24 17:18:33] mautic.ERROR: [MAIL ERROR] Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b7469716fb509668447@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) Log data: >> MAIL FROM:<envios+bounce_605b7469716fb509668447@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) !! Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b7469716fb509668447@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) (code: 0) (send); [EMAIL] {"exception":"[object] (Swift_TransportException(code: 0): Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b7469716fb509668447@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\nLog data:\n>> MAIL FROM:<envios+bounce_605b7469716fb509668447@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\n!! Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b7469716fb509668447@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0) (code: 0) at /home/[USER]/public_html/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Plugins/LoggerPlugin.php:124)"} []
[2021-03-24 17:18:33] mautic.ERROR: [MAIL ERROR] Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b74697b963053665746@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) Log data: >> MAIL FROM:<envios+bounce_605b74697b963053665746@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) !! Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b74697b963053665746@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) (code: 0) (send); [EMAIL] {"exception":"[object] (Swift_TransportException(code: 0): Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b74697b963053665746@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\nLog data:\n>> MAIL FROM:<envios+bounce_605b74697b963053665746@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\n!! Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b74697b963053665746@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0) (code: 0) at /home/[USER]/public_html/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Plugins/LoggerPlugin.php:124)"} []
[2021-03-24 17:18:34] mautic.ERROR: [MAIL ERROR] Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b746a4c1d5083169814@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) Log data: >> MAIL FROM:<envios+bounce_605b746a4c1d5083169814@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) !! Expected response code 250 but got an empty response Log data: >> MAIL FROM:<envios+bounce_605b746a4c1d5083169814@[DOMAIN]> !! Expected response code 250 but got an empty response (code: 0) (code: 0) (send); [EMAIL] {"exception":"[object] (Swift_TransportException(code: 0): Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b746a4c1d5083169814@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\nLog data:\n>> MAIL FROM:<envios+bounce_605b746a4c1d5083169814@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0)\n!! Expected response code 250 but got an empty response\nLog data:\n>> MAIL FROM:<envios+bounce_605b746a4c1d5083169814@[DOMAIN]>\r\n\n!! Expected response code 250 but got an empty response (code: 0) (code: 0) at /home/[USER]/public_html/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Plugins/LoggerPlugin.php:124)"} []
Steps I have tried to fix the problem:
I have changed to SMTP multiple configurations, tried several values for --bath-limit, aumeted the php allow memory upto 1.5GB (1024MB normally), etc.