Want a tool to back up or migrate your Zoho emails, then consider the Sysinfo Zoho Backup Tool which is the best tool for the migrating and backuping process. The tool allows its users to migrate their emails to other email clients or file formats such as PST, PDF, OST, EML, EMLX, Gmail, Yahoo Mail, Office 365, and Yandex Mail. talking about its other features then they are: 

• The tool will remove duplicate Mail and provide the option to remove similar emails from selected folders.
• Mail Filter option to filter Zoho emails between the Start Date and End Date.
• Zoho Mail Backup Software is compatible with all Windows versions.