I have found that just booting into safe mode (hold down the shift key after powering up until you get the logon screen) corrects some unwanted bad behavior. In case you do not know the secret keystrokes, you may want to consider adding 'MAC OX X Keystroke List' into a Google window. And then I rebooted again (for no logical reason) but my BT keyboard now works. I tried many things and I strongly think that this is what fixed the problem - I shut down the machine, powered up and immediately pressed Option-P-R (Zap parameter RAM (PRAM) Hold down until second chime.) Then the system rebooted. As I have 3 BT keyboards and none would work, I quickly discounted the 'bad keyboard' solution.

When I returned, the keyboard would not work. I went on Holiday last week and took my 'it just works' MB Pro with me, leaving my bluetooth keyboard at home.

I had the same problem that was identified in the first post. In the next screen a number will be displayed (ex: 76728282), you enter that number in the keyboard and press enter.Keyboard Again Working For Me (Hope This Helps You).Select and click next, keep pressing the green button.When in discovery mode, you keep pressing the on/off button, soon you’ll see the option “Keyboard” in the “Add a BlueTooth Device” discovery screen.Click “Add a BlueTooth Device” (search).There is only one button and one light, no obvious reset buttons or there is nothing in the forum explaining this. As soon as I click the on/off button, it stays on for couple of seconds and switches itself off. The second problem, the green light in the keyboard was not flashing (discoverable mode). In my case there was a warning sign, I simply uninstalled it and did a hardware scan, which corrected the problem. You can easily verify it by searching “Device Manager” and checking under the section “Blue Tooth Radios”. Luckily I had one, the driver was not installed properly. There was no option to “Add BlueTooth Device”, when I searched. The first problem I’ve faced, I was not sure whether my MacBook Pro had any built in BlueTooth radio. I’m actually typing this blog post using the Apple wireless keyboard paired to my MacBook Pro running Windows 7 via BootCamp. It’s not documented anywhere and no mention about this in the forums. I pretty much gave up at one point this is not going to work.

Wireless apple keyboard not working