Recently when I was on my Mac I had turned off Bluetooth accidentally when I had meant to turn the WiFi off and back on (the WiFi was acting up). I logged off when I had to get off. And since my Mac keyboard is the default Bluetooth connected one that you get when you purchase it, it decided to not work.
When I came back later to finish up some things, I turned on my keyboard and typed my password, but nothing showed up in the box. The keyboard, when I turned it on, the light flashed until I finished typing, the turned off. It didn't type anything into the password box, despite being on.
I replaced the batteries thinking it was dead, but that didn't work either. I have no USB connected keyboard to access my mac, I can't access Bluetooth, and my keyboard wont do jack squat.
I don't know how to log in!
How can I log in when Bluetooth is turned off?
(Also if my explanation doesn't make much sense, I have a video instead. )
Best Answer
You can reconnect your Bluetooth keyboard/mouse by cold starting/rebooting your Mac with the physical power button.
This will trigger the Bluetooth setup wizard and detect the Bluetooth devices and enable the service automatically.
Taken from OSXDaily.com - How to Enable Bluetooth Without a Keyboard or Mouse on Mac