When an email cannot be delivered to a Sentinel Messaging customer for whatever reason, the platform will reattempt delivery of that email as below:
– Immediately, after the first failed attempt, then
– Once per minute for 5 minutes, then
– Every 10 minutes for 30 minutes, then
– Every 30 minutes for 1 hour, then
– Once per hour for 24 hours, then
– Once every 24 hours for 14 days.
If for example, some emails for a particular customer are in the 1 attempt/24hr queue, and a new email is processed and delivered for that customer during that 24 hour window, all email in that queue will then be moved to the 1 attempt/1hr queue again for 24 hours until they are successfully delivered.
Please note: If an email cannot be delivered to the destination server within 14 days by the Sentinel Messaging platform, it will expire and an NDR will be generated and sent to the originating email address.