If you want to convert OST items to Outlook 2013, try the
eSoftTools OST to PST Converter software, which I have used myself. Its features are very easy to understand and use. Using this software, you can convert emails, contacts, calendars, notes, and other data from OST to Outlook.
Also, using this software, you can convert OST files to EML, MSG, EMLX, MBOX, HTML, Vcard, etc. Also, you can convert emails from OST files to PST in bulk. Both technical and non-technical users can use this software, and using this software, you can convert 25 emails for free, that too using the free demo provided.
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