In case you are using lot mailing lists with expected frequent change
of subscribers amount, following scenario might be helpfull for you.
Its written for separate mysql database called e.g. mailing_lists with
two tables, first table ml_addr is for storin...
Symptom: Messages are stuck in the server's outgoing queue. SMTP log
shows there is a permanent error 554 when IceWarp tries to send the
message to the recipient's server.
Cause: The receiving server may reject the message if it does not
comply with RFC...
