All the Calendar’s data lives in your WordPress SQL database. If you use phpMyAdmin, you’ll see all the tables that the calendar creates, which live in the same database as your WordPress instance.
Hope this helps.
I am having the same issue which I came online to find out about, we have events in our calendar that are set to ‘all day’ events that run for about a month, and they disappear as soon as the event begins.
Any assistance would be greatly appreciated, thanks.
http://www.ywamflatheadmontana.org/events/