Can't delete an event in Calendar.
I'm trying to delete an even in calendar but I keep getting an error message that says "You can’t change events in the "Contacts' birthdays and events" calendar. Only the calendar administrator and any delegates with permission can make changes to read-only calendars. To make changes to the calendar, contact the calendar administrator." I'm the only one that uses this computer. Anyone know how I can delete it?
MacBook Air, OS X Mountain Lion (10.8.2)