I would like to suggest Ignissta OST to PST Convert software to Repair OST file and Convert OST file to PST File. This solution will help you and give 100% safe, secure and fast conversion results as compare to others. You download trail version from this link https://www.ignissta.com and convert first 50 Emails, contacts, calendars and other items from every folders. This solution also support multi file conversion such as:

1. OST to PST Conversion
2. OST to MBOX Conversion
3. OST to Office 365 Conversion
4. OST to EML Conversion
5. OST to MSG Conversion