Spam filter / gateway
Trend Micro SMTP Error Codes and Rejection Messages
Trend Micro provides mail security and reputation filtering for businesses, routing mail through its own servers before delivery. Recipients manage allowlists and policy settings.
- Codes on record
- 2
- Responses
- 5
SMTP 5501 response
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 550 across every provider
SMTP 5544 responses
smtp;554 5.7.1 <example@example.com>: Recipient address rejected: BLOCK-SEND-ER.
smtp;554 5.7.1 <example@example.com>: Recipient address rejected: Invalid-Recipient.
smtp;554 5.7.1 <example@example.com>: Recipient address rejected: NO-DOMAIN.
smtp;554 5.7.1 <example@example.com>: Recipient address rejected: BLOCK-RCPT.
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 554 across every provider
Trend Micro bounce questions
›Why is Trend Micro bouncing my email?
Trend Micro provides mail security and reputation filtering for businesses, routing mail through its own servers before delivery. Recipients manage allowlists and policy settings. Match the exact wording of your bounce to one of the 5 responses on this page to find the specific reason and fix.
›How do I get past the Trend Micro spam filter?
Authenticate with SPF, DKIM and DMARC, keep your sending IP and domain reputation clean, mail only engaged recipients, and honour unsubscribes. Trend Micro also publishes postmaster guidance, linked on this page.
