Symptoms
Assume that you migrate a mailbox from Microsoft Exchange Server 2010 to Exchange Server 2013. However, the Outlook client remains disconnected for about 1–2 hours after the mailbox is successfully migrated.
Afterward, the client connects automatically without the need for any changes.
Note If you recycle the Exchange Server 2013 AutoDiscover Application Pool right after the move is complete, Outlook connects as expected.
Cause
This issue occurs because of the AutoDiscover application pool database cache refresh interval is 24 hours.
Note After you apply this cumulative update, the database cache interval is set to 1 hour by default.
Resolution
To resolve this issue, install Cumulative Update 13 for Exchange Server 2013 or a later cumulative update for Exchange Server 2013
Workaround
To work around this issue, recycle the Exchange 2013 AutoDiscover Application Pool right after you migrate the mailbox.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
References
Learn about the terminology that Microsoft uses to describe software updates.
