What should I do if my Mac cannot turn on? How to fix it?

DesktopMac or MacBook won't turn on, or maybe won't start with the Apple icon? Don't worry, although it can be irritating, it's usually fixable.

Here are all the steps you need to take to restart your Mac. Just follow the steps in order, unless your Mac won't boot after a failed OS update. In this case skip directly to step 8.

1. Check if your Mac has power

First, check to see if your Mac is plugged in. It's silly but obvious, but anyone who's gotten technical support knows that you have to fix the obvious problems first.

So, if your MacBook won't start on battery, the battery may be completely drained, or it may have malfunctioned.

If you can't charge or turn on your MacBook with the power adapter connected, make sure it's connected properly and doesn't have any damage. If there are wires lying around, try using a different power cord. Also, check if the port is clean. Accumulation of dust will affect normal charging.

While you're at it, check the external hardware as well. Disconnect any peripherals such as printers or graphics tablets as this can sometimes be the cause. If you have a Mac Mini, make sure the monitor is properly connected and powered.

2. Restart the power supply

The next step is重新启动电源. This completely cuts all power to your Mac and allows you to restart from scratch.

• On the latest MacBook,断开电源线，然后按住电源按钮10秒钟.

• For older MacBooks, 请断开电源线并取出电池至少10秒钟.

• If you are using a desktop Mac,请断开电源线至少10秒钟.

Now, reconnect the power and try to restart the computer. This will bring your computer back to life.

Pressing and holding the power button like this is equivalent to pressing the 重置 button or unplugging. It works on phones, e-book readers, and pretty much any other gadget that doesn't let you remove the battery, so it's a good tip to remember.

3. Boot in safe mode

If your MacBook won't start, try remembering what you did the last time you ran it. Are you installing an application or importing fonts or adjusting the system?

If your Mac shows signs of life when it boots up (won't go past the Apple icon or login screen), booting into Safe Mode may help you fix it.

Press 电源按钮 on your Mac, then immediately hold down the Shift key. Hold it until you reach the login screen, then continue as usual.

Safe Mode runs a bunch of diagnostic tests and then boots up a stripped-down version of macOS. This won't load your startup apps, custom fonts, extra hardware features, or any other basic information.

If your Mac successfully boots into Safe Mode, you can begin uninstalling any new apps, disabling startup items, removing hardware, or undoing any other recent changes that may be causing problems.

4.Reset SMC

The System Management Controller (SMC) controls many of your Mac's essential functions. It handles everything from keyboard backlighting to battery management and what happens when you press the power button.

Resetting the SMC is a great way to fix many problems, including issues with your MacBook not booting or not waking up when you open the lid.

There are several ways to accomplish this, depending on which Mac model you have:

【Desktop】

1. 拔下电源线，然后等待15秒钟。

2. Chong new插入电源线, Ran Ho再等待五秒钟.

3. Restart your Mac.

【2018 MacBook Pro +带有T2Safety core pieceMacBook】

1. Press and hold the rightShift key, the leftOption key (ALT) and the left key for seven seconds control keys.

2. While holding these keys, press and hold电源按钮七秒钟.

3. Release all keys, wait a few seconds, and then reboot.

[MacBook without removable battery]

1. Press and hold the left Shift, Options (ALT) and control keys, and 电源按钮（或触摸ID按钮） while holding 10 seconds.

2. Release all keys, and then restart the computer.

[Old MacBookwith removable battery]

1. 取出电池。

2. Arrangement 并保持五秒钟电源按钮.

3. Reconnect the battery and restart your MacBook.

5.Reset NVRAM or PRAM

NVRAM (Non-Volatile Random Access Memory) is a special part of memory used to store certain settings that your Mac needs to access quickly. While it's unlikely that an issue related to this will render your computer unbootable, there's no harm in resetting it as a precaution.

My older Mac uses PRAM (peripheral RAM) instead, the process for resetting is the same:

1. 按电源按钮, immediately after settling downOption（Alt）,Command,P和Rkey .

2. Even though the Mac seems to restart,请按住按键约20秒钟.

3. If your Mac plays a startup sound, please click on 第二次听到哔声后松开琴键.

4. If your Mac uses a T2 chip, please check第二次Apple图标消失后释放按键.

After your Mac restarts, you'll find that some basic settings, such as the time zone or volume levels, may need to be adjusted.

6. Run Apple Diagnostics

Hopefully now, your Mac is back up and running. If not, you can use the Apple Diagnostics tool to check for hardware issues. This will check for the problem and then suggest a fix or show you your support options.

1. 断开所有不必要的外部设备, such as a printer. If desired, you can keep the keyboard, mouse, and monitor powered on.

2. 按下电源按钮。

3. Hold the D key. Keep pressing it until you see a screen asking you to select a language.

4. Select a language and Apple Diagnostics will start running its tests. These take a few minutes to complete.

Once completed, you will see the test results. Some will suggest a quick fix and offer you a chance to rerun the test. Others will generate reference codes, which you can find on the Apple Diagnostics page. It will also display your Mac support options. If there are no problems, the problem is probably not related to your hardware.

On Macs released before June 2013, you'll getApple硬件测试. You activate it the same way, the principles are the same. Select your language and click 测试 to get started.

Hopefully now, your Mac is back up and running. If not, you can use the Apple Diagnostics tool to check for hardware issues. This will check for the problem and then suggest a fix or show you your support options.

1. 断开所有不必要的外部设备, such as a printer. If desired, you can keep the keyboard, mouse, and monitor powered on.

2. 按下电源按钮。

3. Hold the D key. Keep pressing it until you see a screen asking you to select a language.

4. Select a language and Apple Diagnostics will start running its tests. These take a few minutes to complete.

Once completed, you will see the test results. Some will suggest a quick fix and offer you a chance to rerun the test. Others will generate reference codes, which you can find on the Apple Diagnostics page. It will also display your Mac support options. If there are no problems, the problem is probably not related to your hardware.

On Macs released before June 2013, you'll getApple硬件测试. You activate it the same way, the principles are the same. Select your language and click 测试 to get started.

7. Use Recovery Mode Tools

All Mac hard drives have a special Recovery partition. This is independent of a full macOS boot and gives you a set of tools for repairing your computer.

To boot into recovery:

1. 按下电源按钮。

2. 按州Command和Rkey.

3. 看到Apple图标, release the button.

4. Once it completes booting, you will see a new macOS Utilities menu.

The first thing to try is "磁盘工具". This is a version of the same tool available in macOS that allows you to scan and repair your hard drive or SSD. Select the drive and click on "急救" to start the repair process.

More tools are available through the 实用工具 menu. These include terminals for more advanced users.

8. Reinstall macOS in recovery mode

If you've made it this far, chances are your issue has nothing to do with hardware and isn't a simple software fix. The best solution now is to restore a Time Machine backup, or completely reinstall macOS.

You can do this through Recovery. To get started, 按下电源按钮 and hold down the Command and R keys.

If you have a recent Time Machine backup, you can restore that backup to see if it solves your problem. If not, select Reinstall macOS from the menu.

When you choose to reinstall macOS, you will be given the option to format the disk. If you just want to repair the installation, don't select this option - reinstalling macOS on top of itself is no problem.

Follow the on-screen guide to complete the installation. You need to be connected to the internet as the tool will download the operating system from scratch. If you can't resolve this issue, you may need to enable your Mac to boot from USB.

Check for other warning signs on your Mac

All Macs, whether it's a high-end MacBook Pro or an older iMac, have a reputation for reliability. But they still run into problems.

Although fixing a Mac that won't turn on is usually relatively easy, it's best to check for warning signs and patch the problem before it occurs.

Follow the advice in our guide to discovering and fixing common macOS issues—covering everything from memory to malware—and you'll have your Mac running smoothly and problem-free.