SMTP Status: blocked - no DATA from client

Products

• Email Security.cloud

Issue/Introduction

An email has not been delivered to the recipient. In the Track and Trace, the email  'Log View' shows the following error:

SMTP Status: blocked - no DATA from client

Environment

Email Security.cloud

Cause

The SMTP status 'SMTP Status: blocked - no DATA from client' indicates that the sending client failed to provide the expected DATA command during the email transmission process.
This typically happens during the SMTP transaction between the sender and the receiving mail server.

Resolution

- Confirm that there are no network interruptions causing the connection to drop before the DATA command is sent;

- Verify that there are no firewall rules or security devices (e.g., IDS/IPS) blocking the SMTP communication;

- The error may occur for inbound or outbound message from Email Security.cloud perspective, but should be verified from the sender side;