Outlook Conversations are a great way to keep track of message threads. They can also quickly become full of unnecessary messages.
Use the Conversation Cleanup feature to help identifying redundant messages and moving them to Deleted Items.
To run Conversation Cleanup:
In the Home tab, go to the Delete group, and click Cleanup. You will now have three choices.
Clean Up Conversation reviews the selected conversation and deletes redundant messages within it.
Clean Up Folder reviews all the conversations in the selected folder, and deletes redundant messages within it.
Clean Up Folders and Subfolders reviews all the conversations in the current folder, and any folders it contains, and then deletes any redundant messages it finds.
Messages will only be moved to the Deleted Items folder if they already appear in their entirety elsewhere.
You can change where redundant items are moved by going to File | Options | Mail. Under Conversation Cleanup, you can browse for a different folder in which to move the messages and to customize other settings.
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