If you are using MS Outlook and want to convert your emails, contacts, calendar items etc from OST to PST file, then I recommend you to try vMail OST to PST Converter.
- Convert OST to PST, MBOX, MSG, EML, EMLX, vCard and vCal formats
- Recover all Inbox, Outbox, Sent Items, Drafts, Deleted Items, Contacts, Calendar, Tasks, Notes, Journals etc.
- Supports large size of OST file.
- Export option directly to Office 365 & Exchange Server.
- Compatible with Microsoft Outlook 2016, 2013, 2010, 2007 & more versions.