The keyboard doesn't work?
1. Press Ctrl + Alt + Del (all three keys at the same time) to bring up the Task List. Select any program that says "Not responding" and click the End Task button. Repeat until all tasks are ended. Check periodically to see if the keyboard will work.
2. Check to make sure the keyboard is still properly connected to the computer. If the keyboard has been disconnected, you may have to reboot your computer.
3. If all else fails, then turn the power off. Wait a couple of minutes before turning the computer back on.
One of the dirtiest parts of your computer is the keyboard. Regular cleaning will help keep the keyboard working properly. First, blow compressed air through the spaces in between the keys to remove dust and lint. If you shake your keyboard upside-down this will also remove some of the particles.
Another keyboard problem that could occur is when you turn your computer on and you get a message that no keyboard was detected or you get into Windows but are not able to type. Remove the keyboard connector for the CPU, examine the pins in the connector to ensure they are straight, and then reinsert the connector. Also, check and make sure the mouse and keyboard connectors have not been switched. If the keyboard still doesn’t work try connecting, another keyboard that you know is working. This will determine if you need a new keyboard or if you have a CPU problem.