MS Outlook integrates several utilities and add-ins that help clean duplicate emails in MS Outlook effectively. One such built-in utility is Clean Up that can be executed manually from within the application. To run Clean Up for removing duplicated inbox email messages, follow the steps below:

1.Open MS Outlook 2016
2.Select the Inbox folder that contains duplicated emails
3.Go to Home menu and click on the Clean Up option available on the ribbon. Next, select any one option as per the reason for the occurrence of duplicate items:

- Select Clean Up Conversation from the drop down options that appear. This will delete and move duplicate email messages existing in the conversation to Deleted Items folder
- Clean Up Folder option will allow you to delete duplicate email messages from a particular folder
- Clean Up Folder and Subfolders will clean up folders as well as subfolders

4.Next, right-click the Deleted Items folder and select the Empty folder option to delete the duplicate email messages permanently

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