Karen's laptop has stopped charging. It's 10 years old. Leo says that her laptop has a lithium ion battery and it has probbaly just worn out. They won't take a charge after about 500 recharges, and after 10 years, it's very likely that's what it is. But Windows 10 has a feature in the command line. She can get to it by pressing the Windows key, and then typing CMD and enter. Then she should type "powercfg /batteryreport." This will give her a report on her battery's health. It gets saved to the hard drive and she can open it with her browser. If it's under 10%, it won't hold a charge, and she'll have to get a new battery. But she could also just keep the laptop plugged in without the battery and it will work just fine.