If your HP X360 won't power up, try these quick checks first. They can help determine whether the issue is a simple power problem or something that needs service.
Check the charger and outlet: firmly connect the charger to the laptop and to a known-good outlet. If possible, test with a different compatible charger to rule out a faulty adapter.
Do a power reset: with the charger connected, press and hold the power button for 15 seconds, then release. Wait a few seconds and press the power button again to try turning on.
Look for indicators: note any charging light or laptop LEDs when you plug in. A lack of lights can indicate a battery or charging issue.
Detach peripherals: remove USB devices, docking station, or memory cards, then attempt to power on again.
If it still won't start: the issue may be a dead battery, a faulty charger, or a motherboard problem. Consider scheduling a repair or in-home pickup with Repatch for diagnostics and service.

