If you discover a solution for exporting emails from Outlook to MBOX, the software name is eSoftTools PST to MBOX Converter Software. This is a simple and quick method. Converting PST files to MBOX is straightforward. This software works with all Windows versions, including 10, 8.1, 8, 7, Vista, XP, and all earlier versions, and it provides live previews during the PST to MBOX conversion. The demo version is available to all users. For more effective checking, you can convert up to 25 emails per folder.
Read more:- Convert PST files to MBOX format