Try posting more about the laptop such as it's brand and model. Tell how old and what sort of maintenance you do. I can tell you that one very common tip is this:
A: remove the battery
B: press and hold the power button for 30 seconds to 1 full minute
C: re-install the battery
D: attempt power up again
The battery light on my laptop is on but the system will not power-up? Is there anyone out there that knows what this means?
Lisa

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