Laptop Keyboard Keys Not Working? Software or Hardware, and How to Fix It
When some laptop keys stop working, the first job is to find out whether it is software or hardware. That one question decides whether you need a settings change, a cleaning, or a repair.
1. See exactly which keys fail
Open the keyboard test and press every key. Each one lights up when the computer receives it. Note the keys that never light up, the ones that light up twice, and the ones that only work if you press hard. A group of neighbouring keys that fail together usually points to hardware; one odd key, or a whole type of key, often points to a setting.
2. Rule out the usual settings
- Number keys on the right type arrows instead: Num Lock is off.
- Top-row keys change brightness instead of F1–F12, or the other way round: Fn Lock is on. Try Fn + Esc on many laptops, or change it in the manufacturer’s app or BIOS.
- Keys need a long press to register (Windows): Filter Keys is on. Turn it off in Settings → Accessibility → Keyboard. Holding the right Shift key for eight seconds turns it on by accident.
- Symbols come out wrong (@ and " swapped, for example): the keyboard layout is wrong. Check Settings → Time & language → Language & region on Windows, or Input Sources in Settings → Keyboard on a Mac.
- Mac keys slow to respond: check Slow Keys and Mouse Keys in Settings → Accessibility → Keyboard and Pointer Control.
3. Test outside the operating system
Restart and enter the BIOS or UEFI setup (often F2, F10, Del or Esc at startup on Windows laptops). Use the arrow keys and try typing in any text field there. If the keys work in the BIOS but not in Windows, it is a software or driver problem. If they fail in the BIOS too, it is hardware.
On Windows, you can also open Device Manager, find the keyboard under Keyboards, choose Uninstall device and restart; Windows reinstalls the driver.
4. Clean under the keys
Crumbs and dust under a key are the most common physical cause. Turn the laptop off, tilt it at an angle and brush or use short bursts of compressed air across the keys, holding the can upright. Don’t prise keycaps off unless you know how the clips work on your model; butterfly and low-profile keys break easily.
5. After a spill
Turn the laptop off immediately, unplug it, and turn it upside down in a tent shape so liquid can drain. Don’t switch it back on for at least a day, and don’t use a hair dryer. Sugary drinks leave a sticky residue that can stop keys working even after they dry. If keys still fail after it is fully dry, the keyboard membrane is probably damaged.
6. Plug in an external keyboard
A USB keyboard is a quick workaround and a useful test. If it works perfectly, the laptop’s own keyboard or its internal cable is at fault. Many laptop keyboards are a moderate repair; on some thin models the keyboard is part of the top case, which costs more.
Buying a used laptop?
Run the keyboard test and the full laptop diagnostic before you pay. Sellers often plug in a USB keyboard to hide a faulty built-in one, so unplug everything first.