While don't know about the cause, the quick fix was to blow away the calendar and start with a blank new calendar. Once this was done, everything seems be back to normal.
Of course, there is a painful period to recreate all appointment, and ask all organizer to reinvite me back. Originally, we try to have my old calendar backup and available as shared calendar but found that I can copy back most of the appointments. Export of that old calendar via web gui also result in hang up. Thus, the only way is to recreate all appointment from starts. |