Postfix can't send mails externally

September 6, 2017 101 views
DigitalOcean Applications Security Ubuntu 16.04

Hi everyone,

I installed and configure on Ubuntu 16.04 droplet but it couldn't send email externally.

I've tested this scenarios:

  • Send an internal emails, it works.
  • send an email from gmail or yahoo mail or other email service, it works too, so I receive the email in the appropriate mailbox.

The unique scenario that doesn't work is when i try to send to an external email services such as google, yahoo, outlook or other site.

Looking into the Postfix logs I got the some different error messages:
a. Network is unreachable
b. Connetion timeout

Could you please help me? I already opened a ticket for looking into this issue (ports configuration and droplet exceptions) but I didn't receive any feedback/new about the solution... so I'm considering change my VPS cloud provider.

Could you recommend me any other VPS Could server provider?

Thank you all your help.

1 Answer

Hi! Can you please post the output of the following command?

nc -z smtp.gmail.com 25

If it does not output Connection to smtp.gmail.com port 25 [tcp/smtp] succeeded!, it's possible that outbound SMTP is blocked on your droplet. In that case, the support team will be able to unblock it for you!

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