After a lot of searching and testing with different versions of the Symantec Enterprise Vault plugin with Microsoft Office 2013 running on Windows 8.1 x64, I have found a solution to the issue that has been stopping the Enterprise Vault tab not displaying in Office 2013.
The trick was simple. Install the latest version of the Outlook Plug-in (v11 at the time of writing) then Reset the EV Client by the following method.
1. Close Outlook
2. Open Windows Explorer and navigate to \Program Files\Enterprise Vault\EVClient\
3. Double click on “ResetEVClient.exe”
That’s it. Open up Outlook 2013 and you should now see the Enterprise Vault tab.
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