You don’t know how to convert ost to pst try
SDR ost to pst converter software to convert all ost mailbox items in to pst file this software is convert all corrupted and unmounted ost mailbox items in to pst file this software is support all version 32bit and 64bit ost file this software is convert all ost file items like emails, contacts, calendars, tasks, notes, and many other items in to pst file this software is convert all ost file items using some simple steps. For more info visit this link
https://www.stelladatarecovery.com/email-migration/ost-mails-converter-software.php