I applied the fix, and re-started, and iCal, MacScan and 1Password (and a few others that I cannot remember) would not start, or re-set and re-start. I re-booted into Safe mode (hold down SHIFT key while re-starting), and that seemed to cure the issues. BTW, I had tried to roll back the clock to my nearest earlier snapshot in Time Machine, but the Restore button was grayed out. I guess I am lucky that it was, because the Safe re-boot corrected the issues. But, I wonder why I could not Restore with Time Machine.