Failure Details
Failure details explain why recipients failed or did not produce a successful delivery result.
Open failures
- Open Email Marketing.
- Click the failed count or failure details action.
- Review grouped domains.
- Open Details for a provider/domain.
Fields you may see
- Recipient.
- Domain.
- DSN.
- Delay.
- Relay.
- Provider response.
- Guard or validation detail.
Interpreting failures
| Detail | Likely meaning |
|---|---|
| DNS lookup error | Recipient domain or sender DNS issue. |
| Authentication error | Delivery engine or SMTP provider rejected credentials. |
| SPF/DKIM/DMARC issue | Sender identity is not aligned. |
| No lifecycle event | KumoMTA webhook may not be reaching PING8. |
| Suppressed | Recipient is blocked by suppression/unsubscribe logic. |
Next steps
Fix the root cause, send one test message, confirm telemetry, then retry only the intended recipients. Avoid bulk retry until the one-recipient test passes.