The incoming delivery queue holds mail the filter has accepted but cannot currently deliver to the destination. A queue is different from quarantine: the next step is usually to resolve destination acceptance or connectivity.
IN THIS ARTICLE
01 Find the delivery obstacle
- Open Continuity > Delivery queue - incoming. Filter to the affected domain or recipient and choose Show Results.
- Select a representative queued message and inspect its last delivery response and attempt time.
- Check the destination's availability, mailbox status, storage and any firewall or TLS change.
- Use the configured destination test and have the receiving administrator inspect the corresponding server logs.
- After the cause is fixed, select the affected queued message and use Retry delivery from queue where available. Watch its log for the final delivery result before retrying further items.
02 Monitor the backlog
Track whether the queue is shrinking and whether newly arriving messages deliver normally. A single successful test is useful, but a large backlog may still contain recipients with a separate problem.
Common questions
Should I release queued messages from quarantine?
These are different states. Inspect the queue's delivery error and use the correct action for queued mail.
Can the queue store mail forever?
No permanent retention should be assumed. Check the service's actual retry and retention behaviour and respond promptly to destination failures.
Will clicking retry repeatedly make delivery faster?
Not when the destination still rejects or cannot accept the message. Fix the error first and avoid unnecessary repeated actions.
For an outage, give us the domain, oldest affected time, approximate queue size and a representative SMTP error. If a user has already received a manually resent copy, warn them that the original queued message may still arrive after recovery. Verify duplicates before processing orders or payment instructions.