You can go with the DRS MBOX to Office 365 Migration Tool. It helps you to migrate your data from the MBOX file to the Office 365 mailbox with the help of the working demonstration. Apart from MBOX to Office 365 migration, you can also migrate MBOX to many other email clients using this tool such as Gmail, Hotmail, Yahoo, AOL, etc. This tool is the best alternative for the lengthy and complicated manual approach. Moreover, this tool is designed with advanced features and an interactive GUI to simplify the migration process.