Setting up calendar
I want to see and share ONE calendar on our imac, two iphones and an ipad. I've tried setting icloud as the default and turning off Yahoo, but I don't get the same choices on all four devices. I'm getting multiple errors every time I open Calendar on the desktop saying "The server responded with an error. The event " " was rejected by Yahoo because it already exists."
iMac, OS X Yosemite (10.10.5)