Recurrence end date can not exceed Sep 1,4500 error

I have recently started to get an error 
“Recurrence end date can not exceed Sep 1, 4500 00:00:00., Start date is 12/30/9999 11:59:59 PM, which can’t be greater than 8/31/4500 12:00:00 AM.”
I have checked the appointments that I recently entered and they all have limited duration (i.e… will end by 2050.
Does anyone have any idea how to track down what might be causing this?