post fix problem (emails doesn't send or receive)

a message “smtp error connection to server failed” appears when trying to send a message this happened after updating postfix

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June 5, 2023

Hey @0906610ad3fd40e0b542554a891be3,

What do you see in the logs? The first place you should look at when facing this problem is the Postfix log, which usually can be found in /var/log/maillog, /var/log/mail.log, or /var/log/syslog, depending on your system. Tail the log using tail -f /path/to/log and try sending an email again. See if there’s any useful information in the log output.

Additionally, what SMTP port are you using, is it 25? It’s possible the port is blocked and I would advice using either 587 or 465 depending on your preference.

Anothter thing to check would be your postfix configuration after the update. Look into the Postfix main configuration file /etc/postfix/ Ensure the smtpd parameters are correctly configured. inet_interfaces = all should allow Postfix to listen on all network interfaces.

Use the mailq command or postqueue -p to view the mail queue. If there are many undelivered mails, it could indicate a problem.

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