After transiting from MobileMe to iCloud and setup icloud from my iCal configuration, my calendar appeares unusually. Yesterday there were five different instances of appointments scheduled in ical. Toay I open ical and find appointments disappear. It seems that icloud deleted my ical events on Mac.
Heer is a solution for fix “ical events deleted by iCloud”
* If you have Time Machine backup, find all old calendars with a filename ending in .ics.
* In iCal, click File > New Calendar and creat “On My Mac”. Click Preferences > General, and set “On My Mac” as Default calendar.
* Drag all .ics files into iCal. Click Calendars > On My Mac, and export all events that you’ve just add.
* Now Set the iCloud calendar as the default calendar and import the exported file into the iCloud calendar.
* Delete the “On My Mac” calendar.