Postoffice connector not delivering messages when using external storage


SYMPTOMS

If you are using an external device for storage and queue data for the mail services, you may get the following in your logs:

10/28/16 12:01:00 [5F37FCB84DA94DCA9DDF903947386FFD.MAI] Message does not exist after postoffice level filter for PO=example.com.

But the postoffice does not have any filters, and the queues appear not to be processing.

CAUSE

When the messages are passing through the queues, the services check to see whether messages still exist after filters have been processed (whether third party or internal). If the file does not exist, then it is assumed in some cases that the filter removed the message. When using external storage Microsoft uses a metadata directory cache for performance, which can introduce inconsistent results which affect programs which require consistency in the file data. The cache was introduced in Windows 2008 using SMB 2.0.

It is possible to check to see whether your installation is affected by adding the following Windows registry key and restarting the Postoffice Connector service. The delay is measured in milliseconds:

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Mail Enable\Mail Enable\Connectors\SF]
"Message Check Delay"=dword:00004e20

If your Postoffice Connector Debug log then contains the following, then it is likely to be affected:

[5F37FCB84DA94DCA9DDF903947386FFD.MAI] Message became available after wait for PO=example.com.

RESOLUTION

To resolve you would need to disable the directory caching using the registry key:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanWorkstation\Parameters]
"DirectoryCacheLifetime"=dword:00000000

MORE INFORMATION

A Microsoft article describing the issue can be found at:

https://technet.microsoft.com/en-us/library/ff686200(v=ws.10).aspx



Product:MailEnable (Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: Custom: All Versions)
Article:ME020649
Module:General
Keywords:sophos,antivirus,virus,anti,scanning,plug-in,plugin,
Class:TRB: Troubleshooting (Configuration or Environment)
Revised:Wednesday, February 1, 2017
Author:
Publisher:MailEnable