How long will the system retry sending a message that gets deferred?
Oracle Service Cloud all versions, Outgoing Email
If a message sent from Oracle Service Cloud cannot be delivered immediately to the recipient, the message will get deferred for later sending. The system will retry sending the message 10 more times.
Deferrals occur for various reasons, usually when the recipient server detected too many connections in a short timeframe or too many messages, or when a connection cannot be made to the recipient server (e.g. no MXs for this domain could be reached at this time).
The SMTP logs will contain more details about the reason of the deferral. The logs are internal, therefore, if you need to determine the reason why a particular message is being deferred, please submit a service request to have the SMTP logs reviewed.
For more details on bounced messages, please see Answer ID 2800: Bounced E-mail message handling.