Bluetooth makes life so easy in ways that we don't usually realize. There's a lot riding on Bluetooth of late, especially with features like Continuity, Handoff, file share and more. And then there's iBeacons and several other technologies that depend on Bluetooth LE.
On your Mac, a “Bluetooth Not available” message might show up and it just won't connect. If you are facing this problem, here's how to resolve it.
Method 1: Fix “Bluetooth Not available” Error on Mac
Step #1. Exit any app or System preference that is running on Mac and which was trying to establish connection with Bluetooth.
Step #2. In OS X Finder, press Command+Shift+G.
Step #3. It will launch “Go to Folder” and over there, you type /Library/Preferences/.
Step #4. Search for the file with extension of “com.apple.Bluetooth.plist” and delete it. If there are other files with the same extension, delete them too.
Step #5. Return to desktop and click on the Apple menu.
Step #6. Select Shut Down.
Step #7. After some time, re-start your Mac and re-sync your Bluetooth device.
What this does is, it creates a new .plist file for Bluetooth configuration. Hopefully, this should fix Bluetooth connectivity issues on your Mac.
In the case that method 1 doesn't work:
Method 2: Reboot your SMC
If you are having problems after following the above method, you can try to reset your SMC (System Management Controller). It works differently for different kinds of Macs:
Reset SMC in MacBook or MacBook Pro (with detachable batteries)
Step #1. Shutdown your MacBook or MacBook pro and remove the battery.
Step #2. Remove/disconnect your power adapter.
Step #3. Press down the power key for 10 seconds.
Step #4. Attach the battery and power adapter.
Step #5. Turn on your MacBook or MacBook pro.
Step #6. Boot your Mac as usual.
How to Reset SMC in a MacBook Air, MacBook Pro Retina, or MacBook Pro’s (with non-removable batteries)
Step #1. Turn off your MacBook (any of the above version).
Step #2. Attach the power adapter to your Mac.
Step #3. Press Control+Shift+Option keys and power button together for some time and then release the keys.
Step #4. Start the boot as usual.
How to Reset SMC in iMac, Mac Pro, Mac Mini:
Step #1. Turn off your Mac.
Step #2. Disconnect/remove the power cord.
Step #3. Hold down the Mac power button for 5-10 seconds and then release.
Step #4. Attach the power cables and boot normally.