How to diagnose MTA failures


Various reasons why the MTA can fail and how to diagnose it.


  1. Ensure that any MTA Pickup events have been disabled and antivirus detection has been disabled within the MTA.
  2. The most likely cause of MTA failures is corrupt message command files. Examine the MTA Debug and Activity Logs to determine which message the MTA is failing on.

MailEnable routing uses two files for each mail message. The command file contains the addresses of where the message should be sent to (called the envelope), and the second message is the actual message contents. The Message Command File is located in the Queue\Inbound directory, the corresponding Message file is located in the Queue \Inbound\Messages directory.

It is possible to copy the Message Command File from the Queue Connector\Inbound directory so that the MTA will not attempt to pick it up. The message can then be edited and placed back in the directory.

These command files can become corrupted if the server is restarted whilst writing the command file (although this is rare).


More detailed steps and information on this problem:

The SMTP/MTA/PO Connector Crashes:

Product:MailEnable (All Versions)
Class:HOWTO: Product Instructions
Created:1/05/2003 1:15:00 AM
Revised:Wednesday, May 4, 2016