This section describes how to diagnose and fix problems with enabling archiving for mailboxes.
Work through the following checks to correct the problem:
Is the Exchange Mailbox Task for the Exchange Server running?
The Exchange Mailbox Task does the work of enabling mailboxes, so it must be running.
Does the Enterprise Vault mailbox still exist, or has it been created incorrectly? A problem here normally means that, when you try to enable a mailbox, the message "Failed to enable the mailbox" appears.
Is the Enterprise Vault mailbox hidden from the address book?
Use Microsoft Exchange Server Administrator to look at the properties of the Enterprise Vault mailbox. Make sure that, on the Advanced tab, you have not selected the option to hide the mailbox from the address book.
Is the Microsoft Exchange Information Store service running on the Exchange System?
To enable Microsoft Exchange 2000 mailboxes, the Vault Service account must have permission to modify a user's extensionData attribute. If the account does not have this permission, the message "Insufficient Active Directory Permissions" appears.
To check and modify the Vault Service account permissions
On the Windows Start menu, click All Programs > Administrative Tools > Active Directory Users and Computers.
Right-click the domain and then, on the context menu, click Properties.
Double-click the account to which you want to add the permission.
In the Permission Entry dialog box, click the Properties tab.
In the Permissions list, next to both Read extensionData and Write extensionData, check Allow.
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