Sometimes people who roll out Enterprise Vault when archiving Microsoft Exchange want to 'hide' the toolbar and buttons in Microsoft Outlook. Normally the toolbar will look something like this:
Sometimes people customise it a bit, and remove some buttons, so it looks like this:
But you can completely hide it by modifying the Desktop Policy:
Note: For some of the Vault Cache options, if enabled (and it's not likely to be in this scenario) then you need to also visit the Vault Cache tab.
Then in Outlook all you see is:
Of course when hidden, it still works.. and users will be able to retrieve items fine, and also when they delete items the appropriate behaviour will take place on the archived item (as defined in the policy)