Outlook Express Duplicate Killer can find and remove and merge the duplicate items automatically.

Duplicate Killer is a powerful plug-in for searching, managing and eliminating any type of duplicates (e-mails and contacts) across all or chosen Outlook Express or Windows Vista Mail and Contacts (Address Book) folders. You can customize the way how the program recognizes duplicates and choose between two optimized duplicate search algorithms that will help you find identical data quickly. Choose between an easy one-click duplicate removing-merging process or a sophisticated wizard. You can even save each of your search duplicate settings in the profile that can be processed in one click available from the Outlook Express toolbar, to save your valuable time.The program comes with a lifetime license with one year of free support, updates, and upgrades. Support for Windows Vista.