To lock your computer keyboard, install keyboard locking software such as Keyboard Locker on your computer. When running, this software appears as an icon in the system tray of your computer.
To lock your keyboard, press Ctrl+Alt+L. This locks most keys on your keyboard except for a few key combinations including Ctrl+Alt+Delete and Win+L, and the icon in the system tray shows the change in status. To unlock your keyboard, type the word "unlock". Alternatively, download and install Kid Key Lock on your computer. This utility offers you several keyboard locking options including locking of standard character keys, navigation keys, function keys and certain Windows shortcuts.