MailRetriever is a software tool that allows users to restore email, appointments, tasks, notes and other Microsoft Exchange items from unmounted Exchange data stores. It restores items directly to PST files for portability or back to the original Exchange location. There are two restoration options - redirecting restored items to a recovery folder in the user's Exchange mailbox, or redirecting items to a specified PST file. The tool provides a simple restoration process and can restore single items or entire mailboxes.