The Enterprise Vault system mailbox is a mailbox that is used by the Exchange Mailbox, Exchange Journaling, and Exchange Public Folder tasks when connecting to the Exchange Server.
You must create a system mailbox on each Exchange Server that you want Enterprise Vault to archive.
You are prompted for the name of this mailbox whenever you create an Exchange Server archiving task.
After you create the Enterprise Vault system mailbox, it may take some time for the mailbox to be available. The amount of time depends on configuration options in Exchange System Manager. The mailbox must be available before you add an Exchange Server archiving task.
If required, you can make the mailbox available sooner by manually forcing an update of Exchange Server 2000 or 2003. This is not required on Exchange Server 2007.
To force a manual update of the Exchange Server (2000 or 2003)