Delivery Status Notification (DSN) and Non-Delivery Notification (NDN) Messages

All too frequently, email users are receiving "non-delivery reports" from servers even though no email was sent to the server in the first place. In most cases, the addressee is completely unknown. These reports are not only confusing, but they also flood users' mailboxes with unwanted messages.

The format of delivery status notification (DSN) messages, including non-delivery reports, is defined in the relevant requests for comment (RfC), so every correctly implemented email server (MTA) complies with this format. The advantage of this is that iQ.Suite can recognise such messages and, if necessary, filter them or move them to quarantine. One way of recognising these messages is by examining the "Form". The following mail formula rule identifies NDRs by checking the "Form" field for NDR-specific entries:

_formValue := form;
_isNdr := (@Contains(_formValue; "NonDelivery Report") | @Contains(_formValue; "Delivery Report"));
@If(@isError(_isNdr); @false; _isNdr)

You can move NDRs to quarantine using a simple Wall Mail Job:

• Create a mail formula rule with the formula provided above: