You can use CubexSoft MBOX to PST Converter for Mac to access multiple MBOX files in Outlook 2019/2016/2013/2010/2007/ and all versions below if you're looking for a clever solution. Enough software is available to extract mailbox contents and save them in an Outlook PST file format. Any email program, including Apple Mail, Thunderbird, Entourage, Netscape, WebMail, Eudora, and others, can readily support MBOX files. Users can convert a small number of items from MBOX files into Outlook PST data format using the utility's demo edition. All versions of Windows and Mac OS are supported by this software.

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