New message 'moving calendars to server account' won't go away
I don't get it. iCal has worked so well for me for years, and now suddenly and for no apparent reason, I'm getting this error message, 'moving calendars to server account' for no apparent reason, and it makes the app utterly unusable. I've tried turning it off and on in System Preferences, no luck. Why is this happening? I recently did the upgrade to El Capitan. What can I do to stop it? I'm using the cloud service on all my devices, but losing access on my main computer is a total drag.
iMac (27-inch, Late 2012), OS X El Capitan (10.11)