How to delete duplicate messages in Outlook?

Follow these steps to delete duplicate messages in Microsoft Outlook:

  1. Start Deduper for Outlook (click here to download if you do not have it).
  2. Select Email folder in “Search in Folders” panel.
  3. Click “Search” button. Search should start.
    Note: You can cancel the search anytime and remove already found duplicates.
    Note: Use “Fast” search option to search faster, but if you require more precise comparison of duplicates, use “Detailed” search. Fast search compares only first 255 characters of each field, “Detailed” search compares all data.
  4. If the search does not pick all duplicates, change search settings (click “Search Settings” button). To find more duplicates select fewer fields for comparison. E.g. if you select Subject, all items that have same Subject, but different Body texts are considered to be duplicates. You can then add additional field (such as Sender Name) to compare. Increase the number of fields to be compared until you get the desired result.
  5. To remove the duplicates click “Remove” button. Removal settings (click “Removal Settings” button) can be specified according to your needs.
    Note: In default settings duplicates are deleted to deleted items. Therefore if you made a mistake you can restore them from there.