Document information

Document ID: 4667
Subject: Why are messages sitting in out-bound mail queue
Creation date: 12/14/15 4:35 PM
Last modified on: 3/27/24 11:09 AM


Outbound mail queue

The $INSTALL_DIR\OutboundMailQueue folder is used to store messages that cannot be sent to the final destination on the first attempt. There are several reasons for messages to stay here. Messages that fail to be delivered in the first attempt are saved in this queue. Therefore, if a message is delivered immediately, it won't appear in this folder.


Consider the following reasons for a message to stay here.

  • MX record(s) for the destination server cannot be resolved. If you are using Xeams in Hybrid or Firewall mode and a destined for a local domain is found in this queue, ensure you have added the domain in the local host file. (Server Configuration -> Manage Host Files).
  • Outbound port 25 is NOT blocked. Often, users run Xeams on a dynamic IP address, and their ISP blocks the traffic for outbound port 25. SMTP communication on the Internet always occurs on TCP/IP port 25, and if this port is blocked, messages will sit in the OutboundMailQueue folder forever.
  • The receiving server is either down or not temporarily accepting messages. In this case, the message will get delivered automatically.

By default, Xeams flushes its outbound queue every 30 minutes. Follow the steps below to change this default behavior.

  • Login as admin 
  • Click Server Configuration
  • Modify the values for Retry Interval and Retry Count under the Advanced tab. The product of Retry Interval and Retry Count represent the number of minutes an email will stay in the queue. For example, if Retry Interval is set to 10 and Retry Count is set to 432, Xeams will attempt to deliver a message again after 10 minutes and will do that 432 times which equates to 4,320 minutes or 72 hours.

Investigating Actual Failure Reason

  • Click Message Repository/Manage Outbound Queue
  • Select the Send Now button under the Action column as shown in the image below.
  • The following page will display the actual error message for non-delivery.




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