The best tool to convert OST file to EML format is eSoftTools OST to EML Converter software. You can try this tool for conversion. It can recover corrupted OST files with all mailbox data- inbox, sent-items, draft, notes, task, journal, appointment, calendar, etc. This tool provides multiple formats for converting OST files into PST, EML, MSG, MBOX, HTML, Gmail, vCard, Office 365, etc.
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