This is the most complicated method to transfer MBOX files to Outlook PST format manually. So when you ever want to move MBOX files to PST file format, go with a professional application tool like MailsDaddy MBOX to PST Converter tool.
The software gives a user full support to migrate mailboxes from MBOX to PST format. It maintains an initial folder hierarchy with rich text formatting, inline image attachments, etc. You can use the application on Windows OS and export the mailbox from MBOX to PST.
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