If the computer fails to recognize your keyboard, showing as “Unknown USB Device” or similar: Please save all your work, and then Shut Down the computer – do not set your computer into Hibernate or Sleep modes, make sure you “Shut Down” the computer. Unplug your Cleave keyboard, and do not plug in the Cleave keyboard yet. If you are using a Desktop computer, please plug in any other keyboard. Then turn on your computer, and then sign in if required. When the computer is ready, plug in your keyboard into a working USB port; try different physical USB ports if required. If your computer only has USB Type-C ports, you’ll need an adapter. If using a Mac computer, follow the Keyboard Setup Assistant steps, and then press [Fn][Esc][A] to select the Apple Layout. If after the above the keyboard still doesn’t work, please do the following: With the keyboard plug-in, press the following three keys [Fn][Esc][R] and keep pressing them until all the keyboard lights flash three times. This Resets the keyboard. Allow up to 30 seconds for the keyboard to Reset. If after the above, the keyboard still doesn’t work, please use all of the above instructions to plug in the Cleave keyboard into a different computer. As well, sometimes debris inside the USB ports causes false contacts, so please make sure the USB port on your computer is clean and that the USB port works perfectly with another keyboard. To test the keyboard, press the keys to make sure they send letters/symbols to the computer. If pressing the keys work, but the Backlight is OFF, press [Fn][9] to turn ON the Backlighting. Another option is to upload the newest Firmware into the keyboard. Please follow the instructions found at the bottom of this page under the section “HOW TO UPLOAD A NEW FIRMWARE”. If after the above the keyboard still doesn’t work, test and review if one key is malfunctioning and causing the problem: If using Windows: Download this ZIP file from our website Unzip file. Run application AquaKeyTest.exe If one key is being pressed or malfunctioning it will show in dark gray color. You can also use https://www.microsoft.com/applied-sciences/projects/anti-ghosting-demo; doesn’t work as well as AquaKeyTest but is good enough. If using macOS: Use the Keyboard Viewer which can be selected from the top bar. Review here. If using Linux or other OSes with X Windows: Use xev.