From time to time a question arises around how Vault Cache (or Offline Vault as it was known pre-Enterprise Vault 8) can be disabled just for one user. The answer to that is to use the registry key called OVEnabled.
This can be set in a number of different places, and because of this it actually helps to post another question which sometimes comes up -> How can I disable Vault Cache just on certain machines? For example you may want to stop Vault Cache being enabled when a user logs in to a terminal server, or Citrix server.
So the registry key is called OVEnabled (because its former life of being related to Offline Vault). You set the key as follows:
HKEY_CURRENT_USER \ Software \ KVS \ Enterprise Vault \ Client \ <StoreID Key>
The key is OVEnabled, and you set it to 0 (zero).
If there isn't a Store ID key then it means that Vault Cache and / or Virtual Vault weren't previously set up, so you can set it just at the CLIENT level. When you do it that way it will be copied to the Store ID Key location in the registry key when the Outlook Add-in starts.
If you want to stop Vault Cache for all users on this machine then according to the Registry Key guide you should be able to go to:
HKEY_LOCAL_MACHINE \ Software \ KVS \ Enterprise Vault
.. and set the registry key there. This doesn't work with this key though.
The only way to override the policy for all users on this particular system is to set the key during a local login script. It's a shame it's one of the few that don't appear to work at the HKEY_LOCAL_MACHINE level !
There is one final caveat. Setting the registry key will only work provided you haven't changed the following Desktop setting:
One of the options for that policy setting is to enforce only the policy - registry overrides won't work.