Email duplicates can accumulate in Outlook with the passage of time, especially when you have imported older PST files or have merged email archives. Deletion of duplicates from Outlook will take a considerable amount of time, especially when there are multiple folders to go through.
Another alternative could be to use the Kernel for Outlook Duplicates Remover tool in order to find Outlook duplicates on the basis of information such as subject, sender email address, date and time, body text and attachments. It gives you the choice of two types of searches, i.e. Standard and Advanced, for finding duplicates.
Once duplicates are identified, you can opt to delete, move, copy or mark the selected emails as per your requirements. Another feature of the tool that you can consider trying is its free trial version, which allows you to explore the available options.
Make sure that you have backed up your original PST files before using the tool, and go through the identified duplicates before deletion of any.
