Ben's suggestion will do what you want, but it will also cause Outlook to regenerate the series. If you have added per-occurrence data, such as moving an occurrence to another day, that data will be lost. If you don't care, then follow Ben's advice. If you need to keep the exception data, then create a new calendar folder, switch the calendar containing the event to a table view live Events, copy the event to the new calendar folder, and export that calendar to a CSV. Outlook will ask you for a date range. Specify a starting date on or before the starting date of the event and specify an ending date of the last recurrence you wish to keep. Now, delete the original event and import the CSV into the main calendar. It will import as individual events with the exception data intact, stopping at the last recurrence date you selected when you exported it.
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