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1. For a variety of reasons, users decide to move their IMAP emails to their Office 365 accounts. If you are one of such people, I advise using the simplest and most reliable method known as: IMAP Backup & Migration Software from eSoftTools. With the help of  this single tool, you can easily export emails from any web-based mail application to Office 365 and other IMAP-based email apps. You can also save your emails into many file formats like- EML, EMLX, HTML, MHTML, MSG, MBOX and many more. 

         Know More - Migrate IMAP Emails to Office 365 Account

         https://www.esofttools.com/blog/migrate-imap-email-to-office-365-account/