A custom notice for delivery status in Symantec Messaging Gateway (SMG) would be preferred.
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# THIS IS A WARNING ONLY. YOU DO NOT NEED TO RESEND YOUR MESSAGE. #
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Your message could not be delivered for 0 days, 4 hours, 0 minutes.
It will be retried until it is 5 days, 0 hours, 0 minutes old.
For further assistance, please send mail to <postmaster>
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
<[email protected]>: 421 4.4.0 [internal] no MXs for this domain could be reached at this time
Currently, the text of the delivery status notification (DSN) messages cannot be modified in SMG.