KnowledgeBase Articles » What does "Deferred: Connection timed out" mean?

Wednesday, November 29, 2017, 10:05

What does "Deferred: Connection timed out" mean?

Category: Troubleshooting

Solution ID: 00000308

Summary:

I see messages in the Transmission Log saying "stat=Deferred: Connection timed out with...". What does this mean and what can I do about it?

Answer:

Your PerfectMail server has failed to connect to a remote mail server. After a reasonable time (4 minutes) it has given up trying and issued the "Connection timed out" error message. After an hour or so (as configured in Queue Warning, see below), your PerfectMail server will send you a warning message saying there was a problem. Your server will continue trying to send this message for a few days (as configured in Queue Return, see below), after which it send you a notification that it has given up entirely.

So what happened?

Your server failed to open a connection with the remote mail server. The connection is the first step before the servers can exchange any content at all; literally before they can even say "hello". This is a connection level issue, which means this has nothing to do with either the sender/recipient addresses or the message content. There is nothing more that can be recorded in the log files as there would be no more information other than we couldn't even get a connection.

Possible issues:

1. Your server is blocked by some reputation service, such as https://spamhaus.org;
2. The remote mail server was experiencing network issues or heavy traffic;
3. The remote mail server is limiting connections from your server (hourly, daily, greylisting, etc.);
4. The remote mail server has purposely been configured to not accept a connection from your server.

Solutions:

1. Check to see if you are on an RBL list, such as https://www.spamhaus.org/lookup;
2. Wait a little while and try sending again;
3. Contact the remote mail administrator to see if they are having issues or if your mail server has inadvertently been "black listed".

Tags: email, delivery, mail, queue, deferred, stuck, connection, timeout

Link to this article: kb/deferred_connection_timed_out

Updated: Wednesday, November 29, 2017, 10:05

-- David Rutherford