SMTP Status: 452 4.3.1 Insufficient system resources
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SMTP Status: 452 4.3.1 Insufficient system resources

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Article ID: 152741

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Updated On:

Products

Messaging Gateway

Issue/Introduction

Inbound e-mail is building up in the delivery queue with the Last Error of 452 4.3.1 Insufficient system resources

To From Date Route Size (bytes) Last Error Next Attempt Total Attempts
[email protected] [email protected] Wednesday, Aug 9, 2023 04:30:53 PM PST Default-Local-Route 32345 452 4.3.1 Insufficient system resources Pending 1

Environment

Messaging Gateway (SMG) with on prem Microsoft Exchance 2007, 2010 or 2016

Cause

The downstream e-mail server is responding to the SMG's attempt to deliver messages with "452 4.3.1 Insufficient system resources". This causes the SMG to retry delivery of the message.

This usually indicates that the destination server has run out of disk space or some other resource which is preventing it from accepting email.

Resolution

The SMG appliance is working as designed.  The issue lies with the downstream e-mail server.  Queue errors that indicate an internal problem will have the "[internal]" string added.  You may wish to re-route the messages to a working MTA until the issue with the downstream e-mail server is resolved.