You can disable your laptop keyboard when it is not in use or if it is malfunctioning by the following steps. First method disables your keyboard for single time where the second method keeps it disabled until you revert the changes
1st Method (Temporary)
1. Click START menu and search ‘Device Manager‘
2. Open device manager and double click on keyboard
3. Right click on your built-in Keyboard and select uninstall
This is just one time use because the system will reinstall the default driver on next boot
2nd Method (Permanent)
1. Click START menu and search ‘gpedit.msc’ and open it
2. Click Computer Configuration -> Administrative tools -> System -> Device Installation
3. By clicking on this folder yo will get the contents of the folder in right side of your screen
4. Right Click on ‘Prevent Installation of Devices not described by other policy settings‘
5. Select edit and check enabled option press Apply and OK, Then reboot the system
NB: Revert the changes to use the keyboard again.
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