When you import items into Microsoft Outlook for example by synchronization, duplicates can occur. Unfortunately, there is not an option to remove duplicate items after your import. This article explains howto delete duplicate items after you complete the sync / import process.
1 On the View menu, point to Current View, and then click to change the folder view to a table type view. For example, use the following view and field combinations:
Calendar Active Appointments
Contacts Phone List
Inbox Messages
Journal Entry List
Notes Notes List
2 Right-click a column heading, and then click Field Chooser.
3 From the list at the top of the Field Chooser, click to select the All fields.
4 Drag the Modified field to the table heading.
5 Verify that the duplicate items have a unique date from the original set of items. If it is unique, click the Modified heading so that the items are sorted by this field.
6 Click the first item in the set that you want to delete, scroll to the last item in the set that you want to delete, and then click the last item while you hold down the SHIFT key.
7 Press DELETE to permanently delete all selected items.