I currently sync my office 365-OWA to my microsoft outlook 2011 (mac).  I have also synced an organizing program called curio to my outlook 2011 through iCal. 

A problem came up in that any think that was an all day event or event a present holiday, like new years day would duplicate every time it synced in an exponential manner.  

  In order to work around this, I deleted all of my all day events from all calendars up until 2014 and this work.  However, every time it I open and sync accounts, it is exponenentially duplicating previous and future events beyond 2014.  

Is there any way to stop this?  Either by limiting the dates of syncing calendars or just limit the time period of the calendar?  (I do not need to currently keep a calendar after 2014 and it would be great to archive my old calendar, instead of having it continuously resync and eventually crash my computer.)

Doing this either through OWA or outlook 2011 is fine...I just need it to stop.

Thanks,

Howard