Laptop screen has horizontal white stripe

Problem description:

The laptop screen has horizontal white stripe. The stripe appears as soon as the laptop is turned on and runs even on the initial screen with manufacturer’s logo. When the laptop is booted to the desktop, the image behind the stripe is not visible. The rest of the screen works fine.
In some cases the stripe can be transparent.

Possible cause:

LCD screen failure.

Possible troubleshooting steps and repair solution:

Most likely this problem is related to the laptop LCD screen failure. The screen cannot be repaired and has to be replaced.
You can confirm the LCD screen failure by testing the laptop with an external monitor. The external picture should look normal, without any stripe.