stella ost to pst freeware converter software is the powerful software to convert all ost mailbox items in to pst file this software is convert all corrupted and unmounted ost mailbox items in to office 365 account this software is convert all ost mailbox items using some simple steps this software is support all version 32bit and 64bit ost file this software is install all windows operating systems 32bit and 64bit. For more info visit this link https://www.stelladatarecovery.com/email-migration/ost-to-office-365.php