To pair, open up the Control Panel and go to “Hardware and Sound”. Select “Add a Bluetooth device. When Windows is searching for your Bluetooth devices, put your keyboard into pairing mode (press the button). When it shows up in the list, don’t double click it! Instead, right-click on the keyboard device and select “Properties.” In the window that opens, “Keyboard Properties”, wait a couple of seconds for the services panel to load.
Once it has loaded, check the box for “Drivers for keyboard, mice, etc. (HID)”. Click on “OK” to close the window. Windows will load the drivers for your keyboard. Your keyboard will be paired and should be working with Windows. Try typing a few characters on the keyboard to make sure it’s working properly.