Whilst Enterprise Vault 12 is now available there are still quite a number of people who are on Enterprise Vault 11.0.1. Earlier in the year Veritas released 11.0.1 Cumulative Update 5, for Enterprise Vault. This link has the information about the update. The update is a little over 300 Mb.
A few days ago I was reminded of an old post I wrote (here) that talked about the supported Outlook versions on the Enterprise Vault server.
For a long time Outlook has been used on Enterprise Vault servers to perform various activities relating to archiving. More specifically the underlying MAPI libraries are used. For many years the highest version of Outlook which was supported on the server was Outlook 2007, but recently that all changed.