Here’s a little time-saving tip for working with mailboxes in Exchange 2010. Normally if you need full access to another user’s mailbox in Exchange 2007/2010 you would highlight their mailbox in the Exchange Management Console and the choose “Manage Full Access…” from the action pane. You would have to do this individually for each mailbox that you wanted to manage full access permissions for.
Here’s an easier way to grant full access to a user for every mailbox in a mailbox database. Just edit the bracketed fields below and paste the cmdlet in the Exchange Command Shell:
Get-MailboxDatabase -identity “[mailbox database name]” | Add-ADPermission -user [username] -AccessRights GenericAll
Voila! You now have full access to all mailboxes in the selected database. This even applies to new accounts created after you run the cmdlet.