This is easy to fix. The 'Clear' key on the numberpad gets mapped to the 'NumLock' key on windows. If you want to fix the swapping of the alt and 'Command' keys, KeyTweak works well. It can also let you set the additional F-keys (e.g. F13-F19, which are not real F-keys) to be whatever you want. Got the new Magic Keyboard with Numeric Keypad. Function keys are not working as marked (brightness, volume, etc.). I know instructions say need MacOS 10.12.4 or later. But I have the Magic Keyboard without keypad and it works perfectly - including function keys. Don't understand why I can't use all the functions just because I'm on El Capitan. Most portable computers have a group of keys on the keyboard that can function as the numeric keypad. To find the keypad, look for small numbers or symbols in the lower-right corner of keys on the right side of your keyboard. Press the Num Lock key to turn on the keypad. The green light glows on the Num Lock key when the keypad is active.
Here is your answer - just found it on MacRumors as I was experiencing the same problem. Ready - got a pen and pencil available: Hit 'Clear' lol, yup, that is your on off button for the numeric pad.:-) Be sure to share with others. The 'Clear' Button is located above the number 7. Turn on the keyboard. Press and hold Command + w until the keyboard light begins blinking, indicating the keyboard is ready to pair. Use Windows Bluetooth settings to pair the keyboard, entering the same code (e.g. 123456 Enter) on both internal and external keyboards.
Boot Camp Control Panel User Guide
Apple Magic Keyboard With Numeric Keypad Function Keys Not Working Key
In Windows on Mac, pressing function keys on a portable Mac and some other Apple keyboards controls hardware features. Boot Camp supports the volume, brightness, keyboard illumination, and media keys. Apple pdf viewer.
Magic Keyboard With Numeric Pad
In the Boot Camp Control Panel, you can change the default behavior, so that pressing a function key controls app features, and pressing a function key and the Fn key controls hardware features.
In Windows on your Mac, click in the right side of the taskbar, click the Boot Camp icon , then choose Boot Camp Control Panel.
If a User Account Control dialog appears, click Yes.
Click Keyboard.
Select or deselect “Use all F1, F2 etc. keys as standard function keys.”
Apple Magic Keyboard With Numeric Keypad Function Keys Not Working Independently
Some portable Mac computers have a group of keys with small numbers on them that can be used as a numeric keypad. To use these keys as a keypad, press the Num Lock (F6) key, or hold down the Fn key while you press the keys on the keyboard.
Apple Magic Keyboard With Numeric Keypad Function Keys Not Working Together
See alsoGet started with Boot Camp Control Panel on MacTroubleshoot Boot Camp Control Panel problems on MacApple Support article: Use your Apple Keyboard in Windows with Boot CampApple Support article: How to use function keys on MacBook Pro with Touch Bar