Thank you for the helpful post. I would also like to suggest another application that I used to convert my MDaemon mailboxes to Office 365. You can use it to migrate MDaemon data to PST, PDF, EML, MSG, MBOX, HTML, RTF, DOC, CSV, ICS, vCard, Office 365, Exchange, Gmail, Yahoo, IMAP Server etc. It is simple to use and is also available as a free trial edition for evaluation purpose.
Read more >> https://www.cubexsoft.com/mdaemon/