If you want to take backup and migrate all emails from IMAP to Another server without losing any data. So use the eSoftTools IMAP Backup Software. With the help of this utility, users any users can easily migrate/import IMAP email information to webmail as well as many other formats. It also offers a free demo version for all users to know their Migration process.
Know more:- https://www.esofttools.com/imap-backup-migration-tool.html