If you want to take a backup of your Office 365 Mailbox in Mac OS. You can use Office 365 Backup Tool for Mac, this tool easily works on Mac OS. And it allows you to backup Office 365 emails, contacts, and calendar to PST, MSG, EML, EMLX, and MBOX. The app gives only a few simple steps to achieve migration from Office 365 folder to the required format in any single and bulk mode just a few minutes. The software supports all versions of Mac OS (10.15) "Cataline".