Why is my keyboard not working?

Number lock key is off

If the number pad is not working, make sure the Number Lock key is on. This key can be found right on top of the key that says number “7.” I will read, “NUM LOCK.” Every time you press it, the computer screen will tell you if it is on or off.

It is dirty underneath the keys

Use a cleaning duster spray to clean underneath the keys. Sometimes dirt will get stuck and prevent the keys from being pressed all the way down.

Keyboard is completely nonfunctional

If the keyboard just isn't working, look into replacing the keyboard.

If you're still confused, then check out Toshiba Satellite C55D-A5201 Troubleshooting