Convert Orphaned OST to PST file with PassFixer OST to PST Converter software. With this software, users can easily recover and convert their Outlook OST files. It’s a very powerful tool that comes from PassFixer. It provides many types of file formats to convert Outlook OST files such as EML, HTML, Yahoo, Gmail, Office 365, MSG, ICS, Zimbra, MBOX, and EMLX. The live preview feature helps you to see the preview of your Outlook OST file before conversion. Download the free demo version of this tool and get 25 mailbox items from each folder.

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https://www.passfixer.com/blog/how-to-convert-orphaned-ost-to-pst/