OST To PST File Download Tool - Version 3.0 OST to PST conversion is the process to convert an orphan Offline Storage table (OST) files into Personal Storage Table (PST) file. OST PST tool facilitates users to recover lost emails, contacts, drafts, calendar items, etc. in cases of Exchange Server crash, deletion of Outlook profile, corruption of Exchange database, and deletion of users' mailboxes from Exchange Server. OST file, which is a duplicate copy of user's mailbox on Exchange Server, carries emails, notes, contacts, calendar items, tasks, and other email items. Therefore, it can be used to recover lost email data. Now just download our OST PST file download tool & get rid of OST issues. Purchase full license version only at $249.