Solved! Lenovo ThinkPad t420s not booting on mains power but boots up on battery

[rebeccanyakapembe321]

My Lenovo ThinkPad t420s not booting up on mains power but boots up on battery.the power adapter is okay but the battery is not charging neither is the battery light blinking.please help

 

[robaka777]

if power adapter is different wattage or different brand it will cancel contact with battery, may this would be problem with laptop power on too , try original power adapter