Collect sender, recipient, approximate time and any bounce text. Root-level users can see broader server data, while reseller visibility is limited to owned accounts.

1. Open Mail Delivery Reports and choose the appropriate search field, such as recipient, sender or message ID.
2. Select the delivery type and a narrow date/time range, then run the report. Expand only when the first search does not locate the expected event.
3. Open the matching message details and read its result, router, transport and destination information where available.
4. Use additional columns to identify the sending account, source IP or authentication context when diagnosing an application or compromised mailbox.
5. Correct the evidenced cause and send a new test with a unique subject. Compare its outcome and retain the original message ID for support.

The report should explain whether this server delivered, deferred, filtered or rejected the message. Correlate a queued message with Mail Queue Manager when it still awaits delivery.

A success event at an external destination does not guarantee Inbox placement. Missing records can reflect retention, reporting configuration or a different sending route. Avoid a very broad busy-server query unless necessary, and redact private data when sharing findings.

Ordinary reseller visibility is limited by ownership and privileges. Escalate cross-account or server-wide incidents to the authorised administrator instead of sharing higher-privilege credentials.

• Investigating a growing Exim queue in WHM
• Containing an account that is sending unauthorised email
• Tracing a missing message with cPanel Track Delivery
• Changing a WHM server hostname with DNS and certificate checks

• cPanel: Mail Delivery Reports
• cPanel: Mail Queue Manager