I have a Toshiba laptop. It is about 4 1/2 years old.

My wife and I were on a weekend trip and we used the laptop on and off as we traveled. Everything worked fine all weekend. It worked in the car 45 minutes before we got home, but when I tried to start it up at home, nothing. The battery was probably at 67 percent, so that shouldn't have been an issue, and besides that, it won't do anything plugged in either.

The only issues I've had with it were the hard drive went bad in the first year and was replaced under warranty. Then only a few months ago, the backlight went out on it and was replaced. I suppose it is getting old and has been used a lot, so I should expect problems to develop.

What are the possible problems when a laptop suddenly won't turn on?

Defective power switch. Dirt, lint, and crud in the cooling fan. Failed battery. Failed hard drive in some cases. Failed memory module. Bad power jack (common on some Toshibas) where the jack becomes separated from the system board. Bad power adapter (test with a borrowed one). The ribbon cable from the keyboard/system board to the monitor has come loose (remove and reseat). Water, coffee, soft drink, or alcohol beverage leaked into the keyboard. Failed cooling fan. Heat curled the sytem board and cracked the circuitry.