I want to suggest a tool that can help to remove duplicate emails from Thunderbird directly. Once you can try this MailsClick MBOX Duplicate Remover Tool it will delete duplicate files from Thunderbird mailboxes and other MBOX-supported email clients like Apple Mail, Eudora, Entourage, Spicebird, etc. You can also try this MBOX Duplicate Remover to perform bulk duplicate MBOX files it will help to scan and remove duplicates in just 4 simple steps. Users are free to upload multiple files to scan and delete duplicates. Users can install this software on Windows 10,8,7, XP, and Vista. Use this tool free trial to utilize features.
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