courier-mta (esmtpd) only delivers messages to /var/lib/courier/tmp

I swear that courier-mta was working before, but now it has stopped working. The problem first started out with getting “submit: Permission denied” errors and I was unable to send emails to the machine. I chmod’d /var/lib/courier/tmp (via chmod 771 /var/lib/courier/tmp) which fixed this. But, now all the messages are stuck in /var/lib/courier/tmp/NNNNNN and never…

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