To enable users to access archives and manage archived items from within OWA clients, Enterprise Vault OWA Extensions must be installed on Exchange 2007 CAS servers. For OWA 2000 and 2003, the extensions must be installed and configured on front-end and back-end OWA 2000 and 2003 Exchange Servers. Archives can be searched and items can be archived, viewed, restored and deleted, if permitted. Enterprise Vault buttons and menu items are added to the client. The administrator can configure in the Enterprise Vault Administration Console what functionality is available to OWA users.

OWA users do not require the Enterprise Vault Outlook Add-Ins to be installed on their desktop computers.

The Enterprise Vault OWA 2003 Extensions are also required to support access to Enterprise Vault when using RPC over HTTP connections to Exchange Server 2003. (No server extensions are required to support RPC over HTTP with Exchange Server 2007). RPC users must have the Enterprise Vault Outlook Add-Ins installed on their desktop computers.