> I wonder if anyone can help? I've done a lot of googling but still can't see > anything that relates clearly to my problem. > > When sending a newsletter to clients using Postfix as my MTA, I will get > multiple deliveries of the same email to a user, although they are only > listed once. I have isolated this as an MTA problem with Postfix and it > occurs most often when sending to Yahoo email accts. >
> In logs I get the message that Postfix lost connection with <name of server> > while sending end of data -- message may be sent more than once. > > If this is an issue with the other corresponding server, or nothing that I > can change in Postfix, then I'd rather the email not be sent at all than be > sent multiple times. I'm running Postfix v2.5.1 > > Can anyone suggest what might be wrong?.... thanks. Unfortunately, it's doing exactly what it says it's doing. The transfer starts and at some point before the end of the SMTP transaction, postfix loses the connection (the receiving system disconnects or something in-between like an ill-behaved firewall kills the connection), so postfix has no confirmation that the transfer completed. The message stays queued and the transfer restarts the next time it connects, which gives you duplicate messages. Right now my best guess would be that Yahoo believes you're a spammer and is throttling or tar-piting your connection. Before changing too many setting in postfix (which probably won't help a lot), you should see about getting whitelisted with Yahoo, which would almost certainly take care of the problem. Terry
