When I try to Bluetooth "pair" my new iPad Pro 9.7 (iOS 10.1.1) with my iMac El Capitan (21.5", mid-2011, OS X 10.11.6), I get a "successful connection" message from both devices. But the connection drops out after only 4-5 seconds. Both devices indicate right away that they are no longer connected. I also can't seem to get them to connect via Airdrop, even though Airdrop appears in the iMac's Finder and in the iPad's Share menu. {I thought only "Handoff" wouldn't work on my mid-2011 iMac.} There were no error messages - all indications seemed to point to them staying connected. My iPad also doesn't appear in my iMac's Finder when I connect them using USB. My iPad Pro isn't working exactly the way the Apple Store salesperson said it would easily converse with my "legacy" iMac! Any suggestions please, including any alternative ways to share files directly and quickly between both devices?