Unplug the power. Remove the battery. Hold in the power button for 20-30 seconds. Plug the power cord into a known good electrical outlet (not controlled by a switch), connect it to the laptop and try to power it on. If it doesn't power on, are there any lights? Do you hear the fan try to spin? The lights may assist you - check the manual online. Sounds like it may need a new motherboard, should power cycling it not work.
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Have you tried to remove the battery, try to remove it ad plug it directly without the battery
Unplug the power. Remove the battery. Hold in the power button for 20-30 seconds. Plug the power cord into a known good electrical outlet (not controlled by a switch), connect it to the laptop and try to power it on. If it doesn't power on, are there any lights? Do you hear the fan try to spin? The lights may assist you - check the manual online. Sounds like it may need a new motherboard, should power cycling it not work.