I have an old Compaq Presario CQ62 laptop (64) running Windows 10 Home, which I have only been using plugged in, because the installed battery is dead. It has worked fine for months and months. Today I couldn't get my computer to shut down, so I tried to manually shut it down pressing the power button, but it wouldn't do anything. I also tried clear, alt, delete and nothing, so I unplugged the power source, knowing it would shut down eventually because the battery was dead, and that worked. Now it will not power back up plugged in. It does nothing. No light, no fan, no sound. I tried the whole remove the battery, unplug the power cord and hold down the power button for 30 to 60 seconds, but that didn't work. I also tried another working power cord. I don't want to invest in a new battery if it will not make a difference, but is there a chance a new battery might resolve this, even if it has been working plugged in with a dead battery for so long? Please help!