Duplicates on calendar

[Ron McCarty]

Title: Duplicates on calendar

I am getting many duplicated items on my calendar which I cannot seem to figure out a pattern to.  Some are holidays which show up as all day events several times and then also show up as from 1:00 am to 12:00 am.
Some items are meeting requests.  I thought at first that every time someone confirmed their attendance another entry went on my calendar for that event, but that doesn’t seem to be the case either.  I can delete the duplicates, but would really like to know what is causing them.

Also, on the duplicated items, there is a bar on the left side of the event window.  It is clear on all but one of the duplicates. One is black. I have not idea what this means either.

Ron McCarty
University of Oklahoma