If you want to add Roundcube emails to Office 365 quickly and securely, the CubexSoft Roundcube Backup Tool for Mac & Windows is a reliable solution widely recommended by users. This tool allows you to log in with your Roundcube account credentials, fetch all mailbox data, and migrate emails directly to Office 365 while preserving folder hierarchy, attachments, and email metadata. The process is straightforward—install the software, select Roundcube as the source, authenticate your account, choose Office 365 as the destination, and start the migration. It supports bulk mailboxes, selective email export, and ensures complete data integrity, making it ideal for both individual users and administrators who want a smooth and error-free transition from Roundcube to Office 365. https://www.cubexsoft.com/blog/migrate-roundcube-to-office-365/