Sporadically I get this message posting to Exchange 2013 CU8 and have no idea what it means, if it's good, bad or something to ignore.  It's not affecting e-mail or users that I can tell.

Message: Scenario: UpdateMasterTable. The app master table could not be saved due to a conflict. Mailbox: xxx@yyy.com Error: Property conflict: DisplayName: 'UserConfigurationXmlStream', Resolvable: 'False', OriginalValue: 'Object is null', ClientValue: 'Object is null', ServerValue: 'Object is null'

Detected on: 2015-06-08 06:31:27 EST

This is on a multi-tenant system.  I found one web page, in Russian, with this exact error but it was just a "what is this" message like mine.

Hi,

Are there any other error events in application log?

Based on my researching, this error indicates that outlook are trying to sync the configuration information from the .xml file in roaming folder to server side, but there is a conflict. The reason of the conflict may be multiple clients connecting to server, when they sync the configuration information to server at the same side, it caused the disk read-right conflict.

So if there are no issues with this mailbox and other error events, then we can ignore this error safely.

Best Regards.

This particular server has about 380-400 inbound connections with users in Outlook (2003-2013) and a number of users pulling e-email through POP/SMTP.  The error appears on random accounts, sporadically, 1-2 times a week.

What XML file is attempting to be synced?

I get this occasional warning on the same machine that is throwing these errors:

Scenario: ProcessKillBit. Failed to read killbit list file because of exception System.IO.IOException: The process cannot access the file 'C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\owa\prem\15.0.1076.9\ext\killbit\killbit.xml' because it is being used by another process.

Could the two be related?

We see the message ---  with no error.

Event ID:      3074

Scenario: UpdateMasterTable. The app master table was saved successfully. Mailbox ---

So,...what is that  "app master table" ?

Thanks.

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