Laptop monitor problem

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The monitor on my laptop seems to have lost all brightness. The laptop is still functioning and I can barely make out what's on the screen but only just.

Did a quick Google check and it seems to be a backlight issue. Has anyone else had this problem and is it an easy fix? Some sites mention replacing the whole LCD screen but I'm not sure if it's just going to be easier in the long run to buy a brand new laptop.

The laptop is around 4 years old and I can access files from it by connecting an old monitor to it but I was hoping that there was an easy way of fixing this.