This document describes an issue seen during the Microsoft Exchange Migration process. When using a Single Inbox, it is not unusual for users to migrate mailboxes between different versions of Exchange.
Occasionally, there might be an issue with old messages that are duplicated for an unknown reason. This can follow an attempt to migrate a mailbox from Exchange 2007 or Exchange 2010 to Exchange 2013. However, the migration can occur between any version of Exchange. After migration, it is possible that some users might report an old message that was present before the migration which duplicates hourly in Outlook. New messages that remain after the migration generally do not duplicate. The problem in this example is that the VoiceMessages folder becomes damaged. In order to fix the problem, it is necessary to locate a low level view of the mailbox and delete the VoiceMessages folder.
Follow these steps to address the issue for a specific user:
- Download EWSEditor from Microsoft.
- Run the EWSEditor.exe.
- Choose to File > New Exchange Service.
- Choose Use a specific EWS URL... and enter this URL:
"https://<Exchange CAS Server IP>/EWS/Exchange.ASMX"
- Check the Use the following credentials.. check box and enter your UC service accountinfo.
- Check the Use impersonation to log on to another mailbox... check box, and set the id type =smtp address, set the id = address of the mailbox you want access.
- Click OK.
- Choose Yes when presented with the option Do you want to automatically add the mailbox root to the tree view?.
- Locate the VoiceMessages Folder:
- Right-click the folder and choose Hard Delete.
- Locate the user on the Unity Connection Administration web page.
- Choose to Edit > Unified Messaging Accounts.
- Choose the service being used for Single Inbox.
- Choose Reset under Service Capabilities' next to the option Synchronize Connection and Exchange Mailboxes (Single Inbox).
- Continue to monitor to see if you have any further issues with duplicate messages.