Remove duplicate messages This function removes duplicate messages from the current selection of Apple Mail. This script examines the message headers to determine if a message is a duplicate.
These message headers must match any message in the view. The script flags the message for duplicate and removes it form Mail.
The script displays interactive dialog boxes which allow you to specify whether duplicate messages should be removed or retained. It may also prompt you for each duplicate message it finds while scanning. You can also instruct it to save duplicate messages to an archive folder before they are removed.
This script comes with the source code, so you can edit it as you wish. For more information, please refer to the instructions.