Knowledgebase : Email Response Codes
       
Why do I keep getting a 554 5.7.1: Relay access denied? Proofpoint Essentials is a closed relay system. This means that all mail going through the Essentials platform must have a user associated with the platform, whether that be End-User, alias, or Fun...
The bounceback is required to investigate the logs of the destination SMTP server. Problems of this nature are usually a poor quality SMTP server, a broken firewall or router in place between our servers and the destination server (dropping ICMP packet...
If Proofpoint Essentials users are unable to receive email from certain email addresses, it is most likely an issue with the sending mail server. However there are a few possible areas where this may be a configuration issue on the Proofpoint Essential...
Proofpoint has a block list service named: Proofpoint Dynamic Reputation, or PDR. Proofpoint Essentials utilizes PDR for inbound email. IPs listed on PDR will block a message prior to delivery to the account. IPs listed on Proofpoint's PDR may recei...
The Proofpoint Essentials MTA's will give a _550 user invalid_ response to inbound email sent to a recipient address that has been marked as Invalid by the SMTP Discovery service. _\"550 USER EMAIL ADDRESS IS MARKED AS INVALID\"_ If the email add...
This article aims to give a brief guide on how to understand the information in the Proofpoint Essentials logs. Below are some common examples of the various states email logs can display on Proofpoint Essentials, and some explanations for the informat...