AirDrop does not appear in the Share button
I can easily send a photo from iPhone 6+ to my iMac, but not from the computer to the phone.
AirDrop appears in the left column of the Finder window, and when I click on it, it opens and discovers the phone. That's as far as I can get with it; it won't send a selected item such as a photo to the phone - something that I've been successfully doing all year until I installed El Capitán this past weekend.
I noticed while installing that a popup window appeared stating that Droplr would no longer function. I'm fine with that because I haven't used it.
Personal Hotspot if OFF on the phone.
I've tried toggling between "Allow me to be discovered by" Everyone - No One and Contacts Only. It still doesn't work, and I'm baffled that it doesn't appear in the Share button drop down.
iMac, OS X El Capitan (10.11)