Desktop Mac or MacBook won't turn on，Or maybe it can't be launched via the Apple icon? Don't worry，Although it makes people irritated，But it's usually fixable。
Here are all the steps you need to take to restart your Mac。Follow the steps in order，until the problem is solved，Or jump to the applicable step。
1. Check power connection
•Make sure your Mac is plugged into the power adapter，and the adapter is connected well。For desktop Mac，Make sure the power cord is also connected to the electrical outlet。
2. Restart power
•For the latest MacBook，Disconnect the power cord，Then press and hold the power button for 10 seconds。
•For older MacBooks，Disconnect the power cord and remove the battery for at least 10 seconds。
•For desktop Mac，Disconnect the power cord for at least 10 seconds。
3. Start in safe mode
•Press the power button，Then immediately hold down the Shift key until you see the login screen。
4. Reset the System Management Controller (SMC)
•DesktopMac： Unplug the power cord，wait 15 seconds，then reinsert，Wait another five seconds before restarting。
•2018 MacBook Pro and MacBook with T2 chip： Hold down the right Shift key、Left Option key and left control key for seven seconds，Then press and hold the power button for seven seconds。
•MacBook without removable battery： Hold left Shift、Option、Control and power (or Touch ID) buttons，Lasts 10 seconds。
5. Reset NVRAM or PRAM
•Hold Option during startup、Command、P and R keys，Don't let go until you hear the startup sound。
6. Run Apple Diagnostics
•Press the power button，Then hold down the D key until you see the language selection screen。After selecting language，Start running tests。
7. Use recovery mode tools
•Hold the Command and R keys to boot into recovery mode。Repair your hard drive or SSD using Disk Utility。
8. Reinstall macOS in recovery mode
•If none of the above methods solve the problem，Choose to reinstall macOS。Select Reinstall macOS from the menu，and follow the on-screen instructions。
Go through the above steps，You should be able to fix most Mac won’t turn on issues。If the problem is still not resolved，May require further hardware checks or professional support。
