Other and undefined
General outcomes used when the report does not identify a more specific condition.
This category covers codes 2.0.0, 4.0.0, and 5.0.0 from the X.0.0 pattern, used when the result class is known — success, temporary failure, or permanent failure, respectively — but the report provides no more specific condition. Because the shared subject alone does not reveal which of those classes was returned, retain and read the full SMTP reply or DSN context; this is especially important to avoid mistaking the 2.0.0 success status for a rejection.
Codes in this category
This inventory contains only reviewed codes assigned to this subject. Open a code to see its evidence, diagnostic steps and owner-specific actions.
- 2.0.0Other undefined success statusCode 2.0.0 is a general success status: only class 2 is known, with no more specific status. It is not a message rejection.Delivery status2xx · SuccessRecommended actionCheck the full context
- 4.0.0Other undefined temporary statusCode 4.0.0 is a general temporary failure: only class 4 is known, with no more specific status. The message may be retried in a controlled way.Delivery status4xx · Temporary failureRecommended actionControlled retry
- 5.0.0Other undefined permanent statusCode 5.0.0 is a general permanent failure: only class 5 is known, with no more specific status. Do not retry the same unchanged attempt.Delivery status5xx · Permanent failureRecommended actionDo not retry unchanged
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