Connection to SMTP port 25 failing although not blocked

  • Yes, I know SMTP without encryption on port 25 is not secure, but it is what this specific customer has available.

    Although the TCP port 25 connection out is not blocked on either our server firewall nor on the SMTP server, which we confirmed by telneting to it via the command line on the exact same webserver as the website, when connecting via WP Mail SMTP we get:

    2022-10-04 08:57:36 Connection: opening to smtp.REMOVED.pt:25, timeout=300, options=array()

2022-10-04 08:57:38 Connection failed. Error #2: stream_socket_client(): unable to connect to smtp.REMOVED.pt:25 (Connection refused) [/var/www/vhosts/REMOVED/httpdocs/wp-includes/PHPMailer/SMTP.php line 388]

2022-10-04 08:57:38 SMTP ERROR: Failed to connect to server: Connection refused (111)
Viewing 2 replies - 1 through 2 (of 2 total)
  • Plugin Support David

    (@dpinson)

    Hi there @webdados,

    What I would try doing next is to attempt connecting to another SMTP server, such as an account with SMTP2Go.com. This should help indicate if the issue you’re running into is related to the server you’re trying to reach. If you can connect to a different SMTP server without any issues, it would indicate that the problem is with the SMTP server you’re trying to reach. If you can’t, your host may be blocking remote SMTP connections via PHP. In that case, you would need to reach out to the host so they can look into it to find out why those connections are failing. You can also check with the SMTP host to see if your connection attempts are making it to their server. If they are not, it means they aren’t making it off of your hosting server.

    I hope that helps! Have a great day! ??

    Thread Starter Marco Almeida | Webdados

    (@webdados)

    Nevermind. Our bad. The 25 port was indeed blocked on the outbound connections.

    Thanks!

Viewing 2 replies - 1 through 2 (of 2 total)
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