To transfer emails from a Roundcube account to Office 365, you can rely on the CubexSoft Roundcube Backup Tool. This powerful solution supports batch migration, allowing you to move multiple Roundcube email accounts to Office 365 simultaneously. It ensures secure migration of all email data, including attachments and essential mail properties. Try the free demo version to understand how to migrate from Roundcube to Office 365 at no cost. https://www.cubexsoft.com/roundcube-backup/