Fix for Duplicate Contacts Lists in Outlook

Sometimes you may find that a user has multiple Contacts address books listed in Outlook. This can occur when invalid references exist in the Outlook Address Books.

Remove the invalid reference to a contacts folder in Outlook:

Tools > E-mail Accounts > View or change existing directories or
address books > Outlook Address Book > Change... >

Select the duplicate Outlook Address Book(s) and click Remove Address Book for each duplicate.