ARCHIVED: In Outlook, how do I delete duplicate calendar entries?

On your Exchange calendar, you will occasionally see appointments or other entries accidentally duplicated, possibly more than once. This can happen for a variety of reasons; one common cause is synchronizing a PDA that either has duplicate entries on it or is set to the incorrect time zone. Another is making a mistake while importing from some other source, for example, a backup.

Unfortunately, you'll need to identify and delete these entries manually. However, to make the task easier, you can configure Outlook to display all your calendar items on one long scrollable page, and then select and delete multiple entries at once.

Outlook 2010

1. Select your calendar in Outlook. Then, in the navigation pane, select the Calendar folder.
2. From the View tab, in the Current View group, click Change View, and then click List.
3. Click the Subject column heading to arrange all calendar items by subject.
4. Hold down the Ctrl key while you click each duplicate calendar item in the list. Remember to leave one entry unselected; otherwise, you'll delete all of them.
5. When you have selected all the duplicate calendar items, press Delete.

Note: To prevent duplicate calendar items when importing into Outlook, in the Import and Export Wizard, select Do not import duplicates or Replace duplicates with items imported.

Outlook 2007

1. Select your calendar in Outlook. If you have more than one, select the one with the duplicate entries.
2. From the View menu, select Current View, and then click By Category.
3. Click the Subject column heading to arrange all calendar items by subject.
4. Hold down the Ctrl key while you click each duplicate calendar item in the list. Remember to leave one entry unselected; otherwise, you'll delete all of them.
5. When you have selected all the duplicate calendar items, press Delete.

Some of this information is adapted from Microsoft's Delete duplicate calendar items.