452 4.3.1 Insufficient system resources (in reply to MAIL FROM command)

Exchange Server 2007: How to turn off the Back Pressure feature on transport servers

by Bharat Suneja on March 29, 2007

In reference to previous post titled “Exchange Server 2007 Transport: 452 4.3.1 Insufficient system resources“, the Back Pressure feature, that detects resource pressure on Exchange Server 2007 transport servers and stops accepting new message submission if low on resources, can be turned off. Here’s how to do it:

1. Open the EdgeTransport.exe.config file from \Exchange Server\bin directory using notepad
2. Add the following key+value pair:

3. Save file
4. Restart the Microsoft Exchange Transport Service (MSExchangeTransport):
Restart-Service MSExchangeTransport