I can't get my computer to come on

Please be more specific about what is happening. Try Intel-based Macs: Resetting the System Management Controller (SMC) and Resetting your Mac's PRAM and NVRAM.

if nothing happens after pressing the Power button, then take the computer in for service.

If required.

If you live near an Apple Store, make a Genius Bar appointment to have the computer tested. Supposedly there is no charge for testing. Use 2nd link if not near an Apple Store or aren’t in the US. Hardware Repair - Keeping Confidential Data Safe

Genius Bar Reservation US

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