Messages that are queued for known valid recipients due to temporary issues with the destination route (such as network problems) are automatically retried for delivery at the following approximate intervals:
Delivery Retry Intervals
- During the first 2 hours, delivery is retried at a fixed interval of 15 minutes.
- During the next 14 hours, delivery is retried at a variable interval, starting at 15 minutes and increasing by 1.5 times with each attempt (e.g., 15 minutes, then 22.5 minutes, then 34 minutes, and so on).
- From 16 hours after the initial failure until 4 days have passed, delivery is retried every 6 hours.
- After 4 days, a bounce is generated to the sender. If the bounce cannot be delivered immediately, it will be frozen. After this period, the delivery will be marked as permanently failed. The default 4-day period can be overridden via the Software API to a longer or shorter timeframe.
Message Freezing and Thawing
When a message is frozen (meaning it can neither be delivered to its recipients nor returned to its sender), no further automatic delivery attempts are made. A super administrator can "thaw" (force retry) such messages once the underlying problem is resolved.
Caching Valid Recipients
SpamExperts caches valid recipients for up to 4 days. Once this cache expires, SpamExperts will not queue emails for those recipients and will instead temporarily reject the message, allowing it to be queued on the sending server. The sending server will then automatically retry delivery.
Local Recipients Feature
When using the "Local Recipients" feature, no caching is involved, and SpamExperts continues to accept and queue emails for all specified recipients without interruption.
Gotchas to Avoid
- Monitor the status of frozen messages regularly to ensure timely resolution of delivery issues.
- Be aware of the caching period to avoid unexpected message rejections.
