Internet Accounts Preference Pane/Calendar won't open
When I try to open internet accounts I get an error saying "could not load internet accounts preference pane" Calendar also is efected and will not load.
I decided to make a new user account for my imac and now on the new account every thing works fine, but I still get the same errors when I go back to the original account.
Any ideas what I did to screw things up?
iMac (21.5-inch Mid 2011), OS X Yosemite (10.10.1)