I'm running Postfix. It sends mail to my LISTSERV machine across the network. However, some messages come back as connection refused: Jan 3 09:26:34 mail postfix/qmgr: 964C53589FF: to=<NEWSLETTER@STORE.KNIFECENTER.COM>, relay=none, delay=185126, status=deferred (delivery temporarily suspended: connect to STORE.KNIFECENTER.COM[18.104.22.168]: Connection refused) I get tons (thousands) of these messages a day. Is there a setting in Postfix that is making this connection refused? Or is this something that needs to be fixed on my LISTSERV machine? I don't know exactly what information you guys will need to get a total picture of this problem. Let me know what information you need.