Step Three: Run Disk Utility
- Boot up your computer while holding down Command+R (if you'rerunning Snow Leopard or earlier, find your OS installation disc,put it in the drive, and reboot your computer holding down C).
- Select the Disk Utility Option.
- Select your hard drive, and click "Verify."
These are some of the screens you might seeon your display during Mac startup. Some screens,such as the prohibitory symbol or question mark, mean thatyou need to resolve an issue before your Mac can finishstarting up. For all Mac models, startup is completewhen you see the Finder menu bar, desktop, and Dock.
To load your Mac in Safe Mode, press andhold the Shift key while it boots. You can stop holding the Shiftkey when you see an Apple logo and progress bar. To leave SafeMode, just reboot your Mac without holding the Shiftkey.
If the Mac has a power button on the keyboard, like allmodern MacBook laptops do, this is how you forcibly rebootit:
- Hold down the Power button on the keyboard until the MacBookshuts down completely, this may take 5 seconds or so.
- Wait a few seconds then hit the Power button again to boot theMac.
How to Force Restart Your Mac. Press and holddown the Command (?) and Control (Ctrl) keys along with the powerbutton (or the Touch ID / Eject button, depending on the Mac model)until the screen goes blank and the machine restarts.
Hold down Command and R keys while pressing power buttonto turn on your computer, when you see the Applelogo you can release the keys. In the window, chooseDisk Utility and click continue.
Turn your Mac off by holding down thepower button for a few seconds. Turn on your Mac and holddown the Command and R keys until you see the Applelogo. Then you should see a Mac OS X Utilities or MacOSUtility window. Select Disk Utility, click your MacOS or OSX hard drive and select verify/repair disk.
Reset NVRAM or PRAM on your Mac. If your Mac hasissues related to settings stored in NVRAM or PRAM,resetting it might help. NVRAM (nonvolatilerandom-access memory) is a small amount of memory that your Macuses to store certain settings and access themquickly.
How to enter Recovery Mode. 1) In theApple menu choose Restart, or power on your Mac. 2)As your Mac restarts, hold down the Command (?) – Rcombination immediately upon hearing the startup chime. Hold thekeys until the Apple logo appears.
Reboot your frozen Mac computer.
If your system is not responding, or you can'topen any of the Force Quit menus, you can force the computer toreboot. Press ? Command + Ctrl + ? Eject to force the computer toreboot. The ? Eject key can be found in the upper-right corner ofthe keyboard.Unresponsive Application
- Navigate to the "Apple" menu and select "Force Quit."Alternatively, hold down "command," "option" and "escape"simultaneously.
- Highlight the unresponsive application and click "ForceQuit."
- Repeat the process until all unresponsive applications are shutdown.
Press the Shift+Control+Option keys at the left side ofthe keyboard and the Power button, and hold them all down. Releaseall four buttons at the same time, and then press the Powerbutton to turn the Mac on. On MacBooks with a removable battery,unplug the Mac from its power source and remove thebattery.
What to do if your Mac freezes during softwareinstallation
- Shut down, wait a few seconds, then restart your Mac.
- Go to the Mac App Store and open Updates.
- Check the Log screen to see if files are being installed.
- Try installing the Combo update.
- Install in Safe Mode.
- 6. Make some room.
- Reset the NVRAM.
Here's how to reset a MacBook (or any Maccomputer):
- Hold down the Command and R keys on the keyboard and turn onthe Mac.
- Select your language and continue.
- Choose Disk Utility and click continue.
- Choose your startup disk (named Macintosh HD by default) fromthe sidebar and click the Erase button.
To reboot a frozen computer, press and hold downthe power button until the computer turns off. Once the computer isoff, wait a few seconds, then turn the computer back on and let itstart as normal.
Drain the computer of electricity
Disconnect the AC adapter and remove the battery. Holddown the power button for thirty seconds to drain anyresidual power in the laptop. Without replacing thebattery, plug the AC adapter back into the laptop. Press thepower button to turn on yourlaptop.Repairing a disk
- Restart your Mac, and press Command + R, while it'srestarting.
- Select Disk Utility from the macOS Utilities menu. Once DiskUtility has loaded, choose the disk you wish to repair - thedefault name for your system partition is generally "Macintosh HD",and choose 'Repair Disk'.
If you are still having this issue, try repairingyour disk. Here is how: Restart your Mac, and while yourcomputer restarting, immediately press and hold the Command and Rkeys until you see the Apple logo, then you can release the keys.macOS Utilities will launch.
First, Reset the System Management Controller to Fix theBlack Display on Boot
- Shut down the Mac and connect it to your MagSafe adapter and awall outlet as usual.
- Hold down the Shift+Control+Option+Power button at the sametime for a few seconds.
- Release all keys at the same time, then boot the Mac asusual.
Startup or Restart using macOS Recovery
- Turn on or restart your MacBook and hold down theOption+Command (?)+ R keys.
- Use Disk Utility to erase your startup disk AND any otherinternal hard disk.
- Select your drive's name from the left side list and click theErase.
If a flashing question mark appears when youstart your Mac. If you see a flashing question mark onyour Mac's screen at startup, it means your Maccan't find its system software.
With that out of the way, let's look at the first steps ifyour computer won't boot.
- Check for power supply issues.
- 2. Make sure it's not a slow boot.
- 3. Make sure your monitor or display is functional.
- Eliminate external hardware.
- Reset memory modules and internal components.
- A few more reasons your PC won't turn on.
