To add Roundcube emails to Office 365 account, you can use the advanced CubexSoft Roundcube Backup Tool that is reliable solution with batch mode to migrate unlimited Roundcube emails accounts to Office 365 at once. The program can safely migrate all emails data to O365 from Roundcube account with all attachments and other mail properties. Download free demo edition to know how to migrate from Roundcube to Office 365 without any charges. Read more >> https://www.cubexsoft.com/blog/migrate-roundcube-to-office-365/