Managing undeliverable mail
The Dead Mail tab displays the list of email messages in the dead mail folder.
Unlike the deferred mail queue, the dead mail folder contains copies of delivery status notification (DSN) email messages, also called non-delivery reports (NDR).
DSN messages are sent from the FortiMail unit ("postmaster") to an email’s sender when the email is considered to be more permanently undeliverable because all previous retry attempts of the deferred email message have failed. These email messages from "postmaster" include a copy of the original email message for which the DSN was generated.
If an email cannot be sent nor a DSN returned to the sender, it is usually because both the recipient and sender addresses are invalid. Such email messages are often sent by spammers who know the domain name of an SMTP server but not the names of its email users, and are attempting to send spam by guessing at valid recipient email addresses.
The FortiMail unit can automatically delete old dead mail. For details, see
“Configuring mail queue setting”.
| Alternatively, you can: • To prevent dead mail to invalid recipients, enable recipient address verification to reject email with invalid recipients. Rejecting email with invalid recipients also prevents quarantine mailboxes for invalid recipients from consuming hard disk space. For details, see “Configuring recipient address verification”. |
To access this part of the web UI, your administrator account’s:
• Domain must be System
• access profile must have Read-Write permission to the Policy category
To view or delete undeliverable email, go to Monitor > Mail Queue > Dead Mail.