Mail Queue - There Are Pending Messages



When FogBugz is Not Sending Emails and Notifications and the Mail Queue Information shows you for a longer period that There are xx pending messages that could be a sign that emails got stuck in the outgoing email queue.



This can be due to two main reasons:

  • FogBugz is not able to connect to the SMTP Server
  • The Heartbeat Pinger Service is experiencing issues




FogBugz On-Demand Customers

Verify whether FogBugz can send emails. If these steps did not help, contact us.



FogBugz On-Premises Customers

FogBugz On-Premises customers should use the troubleshooting steps described in the following chapters.


FogBugz is Not Able to Connect to the SMTP Server

For email sending related troubleshooting steps please check the FogBugz is not able to send emails chapter of the Troubleshooting Email Notifications guide.


Heartbeat Pinger Service issues

Heartbeat Pinger is the service responsible for triggering the mail processing queue at regular intervals.

To troubleshoot the Heartbeat Pinger service execute the following troubleshooting steps. If the first one does not solve your issue, process to the next one, and so on until your issue is solved.


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Check that FogBugz Heartbeat Pinger Service is running

Check in your windows services list that FogBugz Heartbeat Pinger Service is running.



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Check the MailQueue table

If you have a lot of records in the MailQueue table, it could be because the FogBugz Heartbeat Pinger service just isn’t running. In this case, restart the service (even if the Windows Services reports it as running). After the service restart, the number of records should decrease.


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Check the Heartbeat URL

The service connects to the “FogBugz URL” set in the site settings and hits multiheartbeat.asp. This URL may no longer be set correctly in case you moved the machine or changed its name. For example, if your site settings say your FogBugz URL is, then the Heartbeat Pinger will connect to


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Check that ixGeneration is Set Correctly

You verified that Hearbeat URL is correct, but you still find in the logs URLs like this:


Verify that ixGeneration was set correctly. It should match the FogBugz version that is installed or was upgraded to.


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Check the Rewrite Rule in IIS

When you request for a secure site only, many system admins rely on the IIS rewrite (traditional) rule to accomplish this.

If this is done incorrectly, it could lead to IIS to stop serving for the heartbeat callback ( and fail (Error 500).

To correct this situation:

  1. Remove all rewrite rules from the FogBugz site.
  2. Implement the redirection by following the instructions on the Configure FogBugz On-Premises to Use HTTPS article.


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Check the Bindings in IIS

There are cases when you want to use multiple instances. To enable this, binding http to an IP or specific domain removing the * can result in stuck emails because the system stops listening on localhost.

Restoring the binding on http to * will correct the issue.



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Check Heartbeat Pinger logs

If the above steps did not help to solve the mail sending issues, enable Heartbeat Pinger logging, and check the log for additional information.


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