You can export Outlook OST files to PST in bulk using the
eSoftTools OST to PST Converter software—a tool that has helped many users resolve their issues. It allows for the conversion of emails, contacts, calendars, notes, and tasks. You can export your data into various formats, including PST, EML, MSG, MBOX, EMLX, HTML, and vCard, or migrate it to platforms like Office 365, IMAP accounts, Gmail, and Yahoo. A free demo version is also available for you to try.
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