This issue is addressed as part of the following release:

Enterprise Vault 10.0
http://www.symantec.com/docs/DOC4441

Enterprise Vault 9.0.3

Workaround for versions prior to 10.0
The following workaround is available for users who experience duplicate items when searching Virtual Vault:
1.  Start Outlook
2.  Choose Tools | Enterprise Vault | Vault Cache Properties for Outlook 2007 and File | Enterprise Vault | Vault Cache Properties for Outlook 2010
3.  Once the Vault Cache Properties window appears, click on the Virtual Vault tab.  This will list any archives that are currently enabled for that user
4.  Uncheck the box next to the archive name for each archive associated with Virtual Vault
5.  Restart Outlook
6.  Once Outlook has restarted, an indexing update request will be initiated. 
7.  Allow indexing to complete without Virtual Vault.  Do not close out of Outlook until Indexing has completed.  When checking the WDS status, the number of items being indexed will decrease.  When completed, WDS status will state 'Indexing Complete'.
8.  Once Indexing has completed, choose Tools | Enterprise Vault | Vault Cache Properties for Outlook 2007 and File | Enterprise Vault | Vault Cache Properties for Outlook 2010
9.  Check the box next to each archive to be included with Virtual Vault
10.  Restart Outlook
11.  Once Outlook has restarted, an indexing update request will be initiated
12.  Allow Indexing to complete with Virtual Vault enabled.  Do not close out of Outlook until Indexing has completed.

Once Indexing has completed both Outlook and Virtual Vault, duplicates should no longer appear within the WDS search results.  If at any time the WDS index is rebuilt, the workaround steps will need to be reperformed.



Symantec Corporation has acknowledged that the above-mentioned issue is present in the current version(s) of the product(s) mentioned at the end of this article. Symantec Corporation is committed to product quality and satisfied customers.

There are no plans to address this issue by way of a patch or hotfix in the current or previous versions of the software at the present time. However, the issue is currently scheduled to be addressed in the next major revision of the product. Please be sure to refer back to this document periodically as any changes to the status of the defect will be reflected here.  Please note that Symantec Corporation reserves the right to remove any fix from the targeted release if it does not pass quality assurance tests.  Symantec’s plans are subject to change and any action taken by you based on the above information or your reliance upon the above information is made at your own risk.