Outlook does not have a simple way to open MBOX files. However, you can attempt certain labor-intensive manual methods that require certain applications to complete.

You can accomplish this by using Apple Mail, Eudora Mail, Outlook Express, and finally Microsoft Outlook to convert MBOX files into other formats. In addition, there is the most recommended utility that lets you convert MBOX files between other formats. Advik MBOX to PST Converter is one such utility that allows you to convert MBOX to PST directly so that you can easily open MBOX file in Outlook Windows. With the aid of these programs, you may export MBOX files directly to various email clients as well.

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