How can I migrate archived MBOX emails to Microsoft 365?

Archived MBOX emails can be migrated to Microsoft 365 by first identifying the MBOX files stored on the computer or exported from an email service. Since MBOX is a file-based mailbox format, Microsoft 365 does not provide a simple native option to directly import an arbitrary MBOX file into an Exchange Online mailbox. The migration process therefore generally requires a third-party migration utility or an intermediate supported format.

The Aryson MBOX Migrator Tool can be used to transfer archived MBOX email data to Microsoft 365. It allows users to select the required MBOX files, connect the destination Microsoft 365 mailbox, and migrate the stored emails along with attachments and folder information. Before migrating a large archive, it is advisable to test a smaller set of emails and verify the resulting data in Microsoft 365.