Laptop powers down suddenly and fails to power up.

I have started to experience this problem recently on my laptop, which is 4 years old now. The screen goes black and the laptop completely powers down suddenly. After this happens, it does not power up at all until I drain the residual power by removing the power cable, and the battery and pressing the power button for 20-30 seconds.

This has become so frequent that it happens almost every day. I would greatly appreciate any help.