The most appreciated tool is
eSoftTools OST to PST Converter Software which can support all versions of Exchange OST. It can
convert OST to PST with all emails of Exchange OST file and it recovers corrupted OST database and this PST to PST Converter software can convert OST mailbox emails, tasks, notes, contacts, msgs, chats, attachments, appointments, calendar, and others. The trial version is provided to export 25 emails from every folder of the OST file. Users can migrate OST to PST and other more formats such as HTML, EML, EMLX, MSG, PST, Yahoo, Gmail, Zimba, MBOX, CSV, vCard, and ICS, etc.
Get Know More Here:- Best Free OST to PST Converter Tool