One or more duplicate calendar entries appear in Microsoft Outlook or the BlackBerry smartphone

• BlackBerry® Enterprise Server for Microsoft® Exchange
• Microsoft® Outlook®

A BlackBerry® smartphone user may encounter a situation where some or all calendar appointments are duplicated. To troubleshoot this issue, the following must be determined to identify what the common element of the duplicated appointments are:

1. Are the calendar appointments that are duplicated single instances or recurring appointments?
2. Were the duplicated appointments created directly by the BlackBerry smartphone user? Are they meeting invites or from a delegate, such as an assistant?
3. Does the duplication happen instantly, or after a set amount of time, or after the appointment is updated?
4. How many BlackBerry smartphone users are affected?
5. Is there third-party scheduling software that also writes to the BlackBerry smartphone user's calendar?
6. Do the duplicated appointments exist only on the BlackBerry smartphone, only in Microsoft Outlook, or in both?
7. Are the RefIDs for the duplicated items different? See KB19187 for information on how to find the RefID on the BlackBerry smartphone.

After determining the common elements for the duplicated calendar appointments, and any triggers that may cause them, further searching of the knowledge base on the BlackBerry Technical Solution Center can be done with the new symptoms.

Resetting the calendar on the BlackBerry smartphone may temporarily clear the duplicates, if the duplicates only exist on the BlackBerry smartphone. However, without determining the cause of the duplicated appointments, the issue may recur. See KB04950 for information on how to reset the calendar on the BlackBerry smartphone.