This article describes the behavior of the Level of Trust Filter with regard to the domain bonus point awarding starting with NoSpamProxy version 11.1.
The bonus points as such can be assigned to the respective domains in two different ways:
- Automatically as a result of an outbound email
- Manually via the GUI (in the Partner menu item) or via PowerShell (Set-NspPartnerTrustDetails).
In order for an inbound email from this domain to receive the stored bonus points, the following conditions must be met (it is an OR operation):
- the SPF check is successful
- the DKIM check is successful
- the DMARC check is successful
- the email is S/MIME or PGP-signed and the signature is valid (and matches the domain in the email header!)
- the IP address appears in the domain properties. This list is automatically populated at night with the IP addresses that NoSpamProxy can read from the MX and A records of the respective domain. However, the addresses are only collected if there is no DMARC record for the sender domain.
Furthermore, please note that if the email domain in the Envelope-From differs from the domain in the Header-From, NoSpamProxy will always use the header domain for the check.
For the scenario described above to work, the action “Check SPF, DKIM and DMARC” (only version 11.1) or the reputation filter (from version 12) must also be activated in every rule in which the Level of Trust is active.
In version 11.x, the action does not affect the scoring, but only logs the data.