Recipient mailbox
Recipient mailbox capacity, state, permissions, and local mailbox configuration.
This category covers three reviewed codes for conditions involving the recipient mailbox: a temporary problem expanding a mailing-list address, a full mailbox, and a message exceeding the length limit set for a specific mailbox. Code 4.2.4 belongs to the temporary class, while 5.2.2 and 5.2.3 describe permanent failures. The category alone therefore does not determine the result class; read the complete code to distinguish a list-expansion problem from missing capacity or a per-mailbox message-length limit.
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.
- 4.2.4Temporary mailing-list expansion problemThe receiving system recognized the destination as a mailing list but could not expand it to recipients during this attempt. The code belongs to the temporary class, so delivery may be retried in a controlled way.Delivery status4xx · Temporary failureRecommended actionControlled retry
- 5.2.2Recipient mailbox is fullThe recipient mailbox has exceeded its assigned quota or reached physical capacity. Code 5.2.2 is a permanent failure, so do not retry the same unchanged send.Delivery status5xx · Permanent failureRecommended actionDo not retry unchanged
- 5.2.3Message exceeds the mailbox limitThe message was permanently rejected because its length exceeds the administrative limit for the recipient's specific mailbox. Do not retry the unchanged send.Delivery status5xx · Permanent failureRecommended actionDo not retry unchanged
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