HP ProBook 440 G6 Not Turning On

Laptop won't turn on when pressing the power on button

The simplest and often an effective solution for your computer not turning on, is to perform a hard reset. This can be done by:

If you see that lights or fans are coming on when you attempt to power on your device, but the screen is not displaying anything, ensure that you turn the device off completely.
You can power down the device by removing any charger you may have plugged in and remove the battery. (see battery removal/replacement guide for steps)
Power down the device by holding down the power button for roughly fifteen seconds.
After you have disconnected the charger and battery, (if you removed the battery) wait a few minutes and then reconnect the battery and charger.

If the hard reset didn’t work, here’s another solution that may help with this issue:

Check that your charger is properly plugged into both the device and the wall securely.
Ensure that the charging light is coming on while the device is plugged in.
If you have ensured that the charger is properly plugged in and the charging light is not coming on, plug the charger into a different outlet.

Check the battery for any signs of damage:

Remove the battery and inspect for metal contact points or any damage. (follow this guide to remove the battery)
Clean them gently with a dry cloth if necessary.
Try powering on the device with just the charger connected (battery not installed). If it turns on, your battery may need replacement.

One of the most common causes of power problems is using the wrong charger or a damaged one.

Make sure to use the charger that came with your laptop or an official HP replacement. Check the model number on the charger, it should match your device's requirements.
Examine the whole cable from beginning to end for any damage (cuts, kinks, or exposed wires).
Check the charger brick. It should not be discolored, warped, or emit any burning smell.