Messages in the outgoing message queue can not be delivered.
It is common that spammers use false or non-existing e-mail addresses or domains in the sender address.
Therefore, an error message is generated stating that the reply mail is non-deliverable.
The real cause is due to the spammer's mail being rejected by the REDDOXX filters and the accompanying notification mail sent by the REDDOXX.
These mails accumulate in the Outgoing Messages queue and are a burden to the appliance.
To correct this, set the "Action" in the Filter Settings from DECLINE to QUARANTINE.
The spam mail will then go into the Spam queue and after 60 days (default value), will be automatically deleted.
No bounce mail is generated during this process.
Please note that in the Black- and Whitelists, also in the User's lists, the "Action" DECLINE should not be used.
REDDOXX recommends setting the "Action" to QUARANTINE.