We have no idea why this works, but plenty of people have vouched for it.

Wait 15 seconds and press the button to restart. Press power button once, Press 'S' (the sleep hotkey), and then hold the power button to perform a hard shut down. This isn't official from Apple, but years of MacBook lore claim that a particular key sequence can sometimes revive a non-reacting blank MacBook Pro screen. If it finds no errors, Apple recommends reinstalling macOS (opens in new tab). If Disk Utility finds errors and repair them, restart your MacBook again afterwards. In both cases, if this recovers your screen, it's worth running Disk Utility to check for errors. If you still see a blank screen after about 20 seconds, it's time to move on. On an older Intel-chipped MacBook Pro, press and hold the power button for about 10 seconds, then press and release the power button and immediately press and hold Command + R until you see an Apple logo or other image. If the startup options window doesn't appear, release the power button and try again. If the options window doesn't appeal, release the power button, and press and hold it again for another 10 seconds. You should see the startup options window, which includes a gear icon labelled Options. On an Apple-chipped MacBook Pro (from the M1 MacBook Pro 13 to the new 2023 M2 Pro and M2 Max models), press and hold the power button for about 10 seconds.

Sometimes a good old-fashioned hard restart is all it takes to fix all kinds of MacBook issues. Still no luck? Then try a forced reset and then start up from macOS Recovery. Once you're screen is back, it's worth running Disk Utility to repair any errors (Image credit: Apple / Future) If you definitely have power, but your MacBook isn't starting up, make sure it's disconnected from anything other than your charging cable and adapter. Peripheral devices like printers, keyboards, external drives, mice and trackpads can all cause potential start up problems. Hit F2 or use the control bar to try increasing the brightness on your MacBook Pro. It’s also possible that you (or your cat) might have unintentionally hit the brightness keys on the keyboard at some point at that you screen is simply dimmed. Check the power indicator light shows so you can rule out a faulty power cable. If you're running on battery, connect your laptop to its charger just in case the battery has run down. It can be a massive relief to discover the issue is something as simple as this. This might seem obvious and you've probably already done it, but just to be sure, do check the power and brightness controls.

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