You want to obtain more information about the outbound spam scanning in Email Security.cloud or you have had emails stopped by the outbound spam scanners.
To provide continuity of service, Email Security.cloud scans all outbound emails and rejects the emails we identify as spam. To help you recognize these messages we send an SMTP permanent error response (5xx) to your message transfer agent (MTA)/email server. We suggest that you set your MTA to generate a non-delivery receipt (NDR) to inform the sender that we have blocked the email as spam.