Mac Won’t Start – How to Fix it

Yesterday the Macbook was working fine, just like every day. Today, it suddenly refuses to respond to the start button. This can be extremely annoying, especially on productive systems. But not responding to the start button is only one problem that can occur on Macs: There can be many reasons why the Mac system won’t boot. We show how you can narrow down the error and possibly start the Mac again.

  • Problem: Mac does not boot at all
  • Problem: Mac starts, but macOS does not boot/crashes
  • Problem: Mac starts, but the screen stays black
  • Problem: Mac starts Windows or gives a cryptic Windows error message

Problem: Mac Not Start at all

If the Mac doesn’t make a sound at startup, there are basically only two possible causes: Either, there is no power – or there is a problem with the hardware. In the best case, however, only the power cable (on desktop Macs) has come loose or the battery has run down overnight.

  • First, check that the power cable is plugged in correctly on the Mac. Typically, it comes loose when the computer is moved.
  • Check if the wall plug is plugged in. This can be accidentally pulled out when vacuuming, for example.
  • If you use a multiple socket with a switch, you should check whether it is plugged in and switched on. There are also sources of error lurking here.
  • If this does not work, try another socket. Check (for example with a desk lamp) whether the socket has power at all.
  • If the lamp doesn’t work either, the fuse has probably blown. Check your fuse box.
  • If other devices have power at that outlet, the Mac may be defective, perhaps from a power surge during a thunderstorm. In this case, the motherboard or power switch could be defective. In this case, take your Mac to an Apple Service Partner.

Problem: Mac Starts, but macOS does not Boot or Crashes

If the Mac starts but does not boot up, the fault is usually in the macOS operating system and not in the Mac hardware. You may have incompatible software installed that is preventing the startup or crashing the startup process. If you see the apple icon at startup but nothing happens afterwards, follow these steps:

  • Turn off the Mac again by holding down the power button for a long time.
  • Now disconnect all external hardware on the USB, Firewire and Thunderbolt ports as well as additional displays and try again. Sometimes external hardware is the cause.
  • If that doesn’t work, you should try an SMC reset. The System Management Controller is deeply embedded in the system and can cause a variety of problems.
  • To perform an SMC reset on a Mac without a battery, simply unplug the power cable for about 15 seconds and then plug it back in.
  • To perform an SMC reset on an older Macbook with a removable battery, disconnect the power cable and remove the battery. Then press and hold the power button for 5 seconds. After that, reinsert the battery and try to start the Mac.
  • To perform an SMC reset on a Macbook Pro with a fixed battery (all models from 2009 onwards), press and hold the [Ctrl] + [Shift] + [Option] keys and the power button on the keyboard on the left for 10 seconds at the same time. After that, release the keys and turn on the Mac.
  • On Macbooks with Touchbar, the Touch ID button corresponds to the power button.
  • If the problem persists and you see the apple icon on startup, you can try safe mode: turn off the Mac again and turn it back on. While doing so, hold down the Shift key.
  • If the Mac starts now, the problem is probably a bug in the macOS system: login objects or drivers.
  • In Safe Mode, remove login objects and drivers that may be causing the problem. Use any existing uninstall files from the software installation.
  • Then restart the Mac normally. The problem should now be fixed.
  • If you are not confident in removing it yourself, you should take the computer to a service partner.

Problem: Mac Starts, but the screen Stays Black

Another common Mac startup problem is that the machine works, but the screen stays black. However, it is often just a system setting. To narrow down the problem, you should do the following:

  • Turn off the Mac by pressing the power button for a long time.
  • For Macbooks and iMacs, disconnect any additional monitors that may be connected.
  • Try again: Problems with external screens are often the cause if the screen remains black.
  • For Macs without a dedicated display (Mac Mini or Mac Pro), check that the display is connected, powered, and turned on.
  • If the Mac screen still does not respond, it may be set incorrectly: For third-party monitors, check that the correct port is selected and that the brightness is set correctly.
  • Reset the monitor if necessary.
  • If the integrated monitor remains dark on Macbooks or iMacs, this can have several causes. First try a PRAM reset:
  • First locate the [cmd] + [Option] + [P] + [R] keys on the keyboard.
  • Turn off the Mac again.
  • Perform a PRAM reset by turning on the Mac and immediately holding down the four keys.
  • Hold them down until the Apple logo appears.
  • If still no image appears, you should try an SMC reset (see above).
  • If the Mac monitor still remains black, there may be a hardware problem with the graphics card, ports, or cable connections in the Mac. Take the computer to an Apple service partner.

Problem: Mac Starts Windows or Gives a Cryptic Windows Error Message

When using Bootcamp to run Windows on the Mac, there are a variety of error sources. One of them is Bootcamp itself, which you may have accidentally used to wipe your Mac when installing Windows. But we don’t have to assume the worst: When Windows boots automatically or reports an error, the cause is usually mundane: An incorrectly set boot drive.

  • Turn off the Mac by pressing the power button for a long time.
  • Disconnect USB sticks and external hard drives.
  • Restart it. Keep the [Option] key pressed while doing so.
  • The Mac now offers several options (macOS, Windows, Recovery).
  • Select macOS with the mouse or the arrow keys and press Enter.
  • The Mac should now boot normally into macOS.
  • Open the Mac System Preferences and select “Startup Volume”.
  • Select your Mac system here and click “Restart”.
  • From now on, the Mac will boot macOS again.
  • You can start Windows by holding down the [Option] key during startup.
  • Windows via Bootcamp works independently from macOS. If Windows does not want to boot after selection, you have to fix the Windows boot problems.