Do you want to import OST to Thunderbird? You can try the eSoftTools OST to MBOX Converter Tool. that can recover data from the corrupted OST file into a new Thunderbird file and other EML, EMLX, vCard, vCal, MSG, and MBOX format with all mailbox item Emails, inbox, outbox, sent-items, deleted-items, drafts, contacts, calendars, notes (to, cc, bcc, subject, date and time). The utility works effectively with all editions of MS Outlook including Outlook 2003, 2007, 2010, 2013, 2016, 2019, etc.

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