SMTP Mailbox: DSN Tab

Possible received Delivery Status Notification action (status) values:

delivered: message delivery has succeeded. No further DSNs are expected.
failed: message delivery has failed. No further DSNs are expected.
relayed: message has been relayed or gatewayed into an environment that does not support DSNs. No further DSNs are expected.
delayed: message delivery is delayed. Further DSNs are expected.
expanded: message delivery has expanded to multiple recipient addresses. Further DSNs are expected.

Requested DSNs are returned back to the VersaLex application in a separate SMTP session. When a DSN has been requested as part of a sent message, the VersaLex application retains the original message and tracks message delivery based on the SMTP properties specified. See Specifying Local Listener advanced properties.

Message delivery status and received DSNs can be viewed in the Local Listener SMTP Server DSNs tab. See Working with DSNs.

Please note that not all SMTP servers support or honor DSN requests. DSNs are not non-reputable because they are not signed. The return of the entire original message in the DSN is meant to happen only upon failure, and only when requested. Some SMTP servers always return the entire original message in the DSN regardless of failure status and regardless of whether only message headers were requested.

If the entire original message is included in a DSN received by the VersaLex application, it will strip the payload out of the DSN while saving the DSN to the received/ folder. (The VersaLex sentbox can instead be used to permanently save sent payload.)

Since the VersaLex SMTP server only acts as a mail endpoint, it only generates 'delivered' DSNs.

Return a DSN on success or failure: Request a Delivery Status Notification for each To recipient of a message (Cc and Bcc recipients are not included) and enable other fields on the tab.
Return message headers only
Return entire message: Indicate whether the returned DSN should include just the original message's outer headers or the entire original message.
Also return a DSN on delay: Requests that an intermediate DSN also be returned when a message's delivery has been delayed for an unusually long period of time.