You can also use eSoftTools OST to PST Converter tool to convert bulk Outlook ost files to PST format, which includes addresses, contacts, calendars, projects, notes, and other items, as well as attachments. It has a very basic user interface, but even non-techies can appreciate the software's operating process and capabilities.
Read More:- Convert bulk Outlook OST files to PST
stella ost to office 365 converter software is the most advance software to convert all ost mailbox items in to pst file this software is convert all ost mailbox items like email items, contacts items, calendars items, task items, notes items and many other items in to office 365 account this software is convert all ost mailbox deleted items data in to pst file this software is convert all corrupted and unmounted ost mailbox items in to pst file this software interface is very simple to convert all ost file data using three simple steps and support all version 32bit and 64bit ost file. for more info visit this link https://www.stelladatarecovery.com/ost-to-pst-converter.html
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