Laptop not unlocking

Hi,

Remove the AC and battery. Press the Power button for 30 seconds. Reinsert back the AC and battery and try turning it on. If the problem persists, try these other solutions.

If your Compaq Presario CQ40 is failing to turn on properly, here are a few strategies you could try:

Make sure your laptop is connected to an electrical source and its battery fully charged; an uncharged battery could lead to serious problems for the laptop.

Implement a hard reset by disconnecting both power adapters, unplugging batteries (if available) and holding down power button for around 30 seconds before reinserting them and trying again with power adapter and battery plugged back in.

Check for loose connections and ensure the power adapter is securely attached to both the laptop and power outlet.

If none of the solutions above work, there may be a hardware issue and it would be prudent to consult a technician or manufacturer's support for further assistance.