My MacBook keyboard doesn't respond

The first solution is to disable the mouse keys. But how do I log in with my password if my keys don't work? I have a simple trick: connect a USB keyboard. Now that I am logged in, I can turn off the mouse keys step by step.

1. I click the Apple logo and choose 'System Preferences'
2. I click 'Accessibility'
3. In the next window, I scroll to 'Mouse and trackpad'
4. Finally, uncheck the 'Activate mouse keys' box. The keyboard should work again. Don't they? In that case, I have another tip.

The 2nd solution? Clean the keyboard. This is often the solution when only a few keys don't work. There's probably some dirt behind the keys. I clean the keyboard with compressed air. To check the airflow, I use the nozzle for the compressed air. When I use the compressed air, I keep the nozzle about 1 inch away from the keyboard. Note: I don't hold the sprayer upside down when spraying.

1. I hold my MacBook at a 75-degree angle.
2. I clean the keyboard with compressed air. I move from left to right.
3. When MacBook is on its right side, I once again spray the keyboard from left to right.
4. I repeat this again when MacBook is on its left side.

Voila, the keyboard is clean again!