Use this third party tool Regain OST to PST Converter Software that can easily Export & Convert OST to PST. This Software Repair your corrupt OST emails and Recover deleted OST file data items like: emails, attachments, contacts, notes, calender and journals etc. with this software you can save your OST emails into multiple file formats like: PST, EML, MSG, MBOX, HTML, ICS, VCARD formats. You can see the Preview of Scanned Emails in Preview items before Conversion.