Type Alias DeliveryStatus

Represents whether the message has been successfully delivered to the recipient. This MUST be one of the following values:

• queued: The message is in a local mail queue and the status will change once it exits the local mail queues.
• yes: The message was successfully delivered to the mail store of the recipient.
• no: Delivery to the recipient permanently failed.
• unknown: The final delivery status is unknown.

Represents whether the message has been displayed to the recipient. This MUST be one of the following values:

• unknown: The display status is unknown. This is the initial value.
• yes: The recipient's system claims the message content has been displayed to the recipient.

The SMTP reply string returned for this recipient when the server last tried to relay the message, or in a later Delivery Status Notification (DSN, as defined in RFC 3464) response for the message.