NSF Duplicate Remover Tool quickly remove all kinds of duplicate items like
Contacts, Tasks, Calendar, Notes and Email folders in one click. The utility
also well supports by all versions of Lotus Notes and Windows Platform.
If you want to remove duplicate items by itself, then I suggest you to use a
manual trick that doesn't require any third party tool and effectively remove
all duplicate items from the Lotus Notes NSF files. Get more information about
manual steps, here:-
http://migrateemails.com/2017/03/27/remove-duplicate-items-from-nsf-database-files/