> I'm hoping someone knows the key to this. > > I use a backup MX service to accompany my Postfix mail server. Right now > the Backup MX service has more than 1,200 messages waiting to be > delivered. As near as I can tell (from the Postfix logs) all of them are > addressed to addresses that either never existed or no longer exist. The > Postfix log indicates it is bouncing them with a 450 (temporary bounce) > instead of a 550. So the Backup MX service is keeping them and > continually trying to re-send. > > I've checked the main.cf. The following two lines are as listed in the file: > > unknown_local_recipient_reject_code = 550 > soft_bounce = no > > To complicate things further, when I sent a test message to an invalid > address, I quickly get a 550 response. It appears it's giving 450 > responses to some senders and 550 responses to others, even when the > same invalid address is used.
You have reject_unverified_recipient enabled and the verification is failing. Terry ---------------------------- smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, check_client_access hash:/etc/postfix/access, reject_non_fqdn_sender, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_unauth_pipelining, reject_unauth_destination, *reject_unverified_recipient* http://www.postfix.org/postconf.5.html#reject_unverified_recipient
