The HP Probook series has an indicator light near its mouse pad, or the touchpad. Its main function is to keep your laptop computer safe. If the yellow/orange/blue light is ON it indicates that your touchpad is locked. This disables the pointer and use of the touch pad; it is not an error and it is not a hardware failure as a result of a virus attack. It just means that your HP laptop computer has a system hardware timed program. The sensor LED light needs to be switched OFF in order to activate the touchpad. Double tap the sensors, or the touch pad, to unlock it, and as soon as you do so, the light will switch itself off.
The touchpad on my laptop is locked and there's no keyboard hotkey to unlock it.
Next to the touchpad, there is a small LED (orange or blue)
In fact it is a sensor, simply double tap on it to unlock the touchpad
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