If you can’t access your OST file and want to Transfer/Import Outlook OST to Office 365. In this situation, you can try the best third-party tool eSoftTools OST to Office 365 Converter tool. It can migrate all data into a fresh Office 365 folder with all email properties like to, cc, bcc, subject, time, date, etc. if users have a lot of data and they want to recover only specific mail so they can select single as well as multiple files for the conversion. A free demo file is also available to Import Outlook OST to Office 365 format.
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