Want to learn an easy method for importing Outlook to MBOX with a complete database, then you can use PST to MBOX Converter. It can export emails, contacts, notes, calendars, etc. from Outlook PST files to MBOX format with precise details. Moreover, the tool supports batch migration of unlimited PST files to MBOX files at once. Download a free demo of the tool & understand the complete process for how to migrate PST to MBOX. Refer:https://www.sametools.com/convert/pst/