- 1. Mac Files Tips
- 2. Mac Software
- 3. Mac Storage Tips
- 4. Mac Troubleshooting
- 5. Mac OS
Readkit 2 4 3. Jun 14, 2020 Holding the 'alt' (option) key should open Apple's native boot menu. That should list available drives to boot from. If you still can't boot from the USB flash drive, verify that you created the Mac OS installer on the USB flash drive while working in the same (or as close to) current Mac OS as you intend to write to the USB flash drive. Some users have problems creating a successful bootable USB flash drive because they attempt to follow Apple's instructions on older versions of Mac OS X that require Disk Utility, not the Terminal window 'createinstallmedia' command, to create a bootable USB flash drive.
by Jenefey AaronUpdated on 2020-01-10 / Update for OS X
- Your Mac and OS X have a variety of startup keys and key combinations you can use to affect how the device starts up. Shift key, for instance, starts your Mac in Safe mode, and C (or c) starts up.
- The OS on my Mac recently stopped working and in order to fix the issue I needed to use a bootable USB drive to reinstall the OS. I'm going to take you throu.
You may need to boot up your Mac using an external drive or boot volume once in a while, rather than using a start up disk. Booting with an external disk has a lot of significance. Maybe you want to troubleshoot some problems, repair the disk, do partitions, format the entire disk, update, and install OS X etc. All these are executed perfectly when you use an external boot volume to boot up your Mac. In this article, we are here with the detailed step by step guide on how to boot Mac from external hard drive easily. So, let's get started…
Part 1: How to Boot Mac from USB Drive/CD/DVD
Actually, it is possible to boot Mac from external drive or a hard drive, but there are a few specific requirements needed for your Mac to become eligible for that process.
- First, you have to have an Intel-Based Mac.
- Second, the CD or DVD you are using to boot must contain Apple’s Super Drive or if you are using a USB drive then it should be formatted with GUID Partition, and you are also required to install OS X installer. Apple is against booting Mac from an external storage device, because you may install an older version of OS X than the one you were using.
Boot from CD or DVD:
If you want to boot your MacBook/Air/Pro/iMac from an optical media like CD or DVD you need to follow the steps below:
1. Open your Mac or restart the device if you were already using it.
Boot From Usb Drive Mac
2. When the startup music is playing press and hold the “C” key from the keyboard.
3. This will start the OS X installer from the CD/DVD on your Mac.
So, it is not too complicated to Mac boot from CD/DVD. You can easily burn a bootable image of OS X on a DVD by using Disk Utility.
Boot from External USB:
Using your USB drive to boot Mac is not as simple as you think. You need to prepare your USB drive beforehand for this specific purpose. You have to format the USB drive and insert the proper Operating System, which is OS X.
1. Turn on your Mac.
2. As soon as the startup music begins you need to press and keep holding the 'Option' key.
3. After that release that key, the Startup manager will be launched.
![Mac Mac](https://www.wikihow.com/images/thumb/2/23/Make-the-Heart-Symbol-Using-a-Computer-Step-4-Version-2.jpg/aid151153-v4-728px-Make-the-Heart-Symbol-Using-a-Computer-Step-4-Version-2.jpg)
4. Startup Manager will begin scanning your device and you will be provided with a list of devices that are connected to your Mac.
5. Now, select the drive you want to use with your mouse.
6. Finally, press 'Return' key on the selected option to boot Mac.
This way you can boot your Mac with an external USB drive, but the most critical part is to prepare the USB drive. If you have multiple USB drives connected, then the Startup Manager shall list the drives with the bootable OS. So, this is how to boot Mac from USB drive.
Part 2: Common Problems and Fixes When Boot Mac from External Drive
You may face several issues during MacBook Pro Boot from USB or any external drive. So, a few FAQs are mentioned below which may help you when you are facing any difficulties.
- 1. Have you tried connecting to a different USB port?
- 2. Have you formatted the USB drive with GUID partition?
- 3. Is your Mac shutting down after connecting the disk?
- 4. Is your Disk needs repair?
- 5. Have you connected the USB drive properly?
If you are unable to startup the installer after connecting the USB drive to your Mac, then first you should try connecting it to a different USB port. It may fix the problem.
If you are having problems with your USB storage device then you need to make sure that if you have properly formatted the drive with GUID partition. You have to do it properly otherwise the Intel-Based Mac won't start.
Actually, the MacBook contains a preventive measure and because of that computer shuts down automatically when a damaged USB drive is connected or if the USB port itself is damaged.
If your Mac fails to boot from an external drive even though you have properly installed the OS X installer, then maybe your disk is damaged. You should open Disk Utility and ask permission to repair disk.
There are two types of Apple keyboards, Wired and Wireless. There are also some keyboards with inbuilt USB ports but they may not have enough power to run the drive.
So, this is how to startup Mac from external drive. Follow the frequently asked questions to clear any doubts that you have while booting from external hard drive Mac.
![Apple Mac Boot From Usb Apple Mac Boot From Usb](https://i.ytimg.com/vi/xDkCsVlkkG8/maxresdefault.jpg)
In case, you want to recover any lost or deleted Mac files after a boot, we highly recommend you to go for Tenorshare Any Data Recovery for Mac. It is a utility data recovery tool capable of recovering any type of data from Mac with ease. Go for it!
Recover Unlimited Mac Data for You
- Recover data deleted, formatted or lost on Mac;
- Restore files from hard drive and external storage devices;
- Recover data from failed/crashed/dead MacBook;
- Fully supported latest macOS 10.15 Catalina;
Every operating system can crash at one time or another. While it's safe to say that macOS is more stable than Windows, it can still be affected by issues that prevent your computer from booting up. In such cases, you might need to boot your Mac from a USB flash drive to fix the problem. This article shows you two ways to boot Mac from external USB stick, as well as some troubleshooting tips in case Mac won't boot from the target USB.
Boot Mac from USB Option l: Startup Manager
If your Mac won't boot up normally, you can set it to boot from a different drive, such as a USB stick containing macOS installation files in bootable format. The drive will have to contain a version of the OS that is compatible with the Mac. As long as you have the bootable installation USB, you can start your Mac from the USB by accessing the Startup Manager. Here are the steps to be followed:
Step 1: Insert the bootable USB into Mac and power it on.
Step 2: As soon as the startup process begins, hold down the Option (alt) key and keep it depressed until you see the Startup Manager on your screen. If there is a firmware password on your Mac, hold down the Option key until you're asked to enter that password.
Step 3: You will now see the various startup disk options, and your USB will be listed there. If you click on the Up arrow right below the icon for the USB, the computer will only startup once using this disk. If you press and hold down the Control key while making your selection, it will be saved, and your computer will boot from the USB every time, as long as it is left in the computer.
At this point, you can also use the Mac installation disk to boot your Mac from. It will appear as EFI Boot, and it works on all computers running macOS 10.9 or higher.
Boot Mac from USB Option 2: Safe Mode/Recovery Mode
As an alternative, you can start your Mac in Safe Mode (Recovery Mode). This will allow the system to automatically detect and repair directory issues. Safe Mode will only allow required kernel extensions to load, preventing login items and startup items to load automatically. It can also help you isolate the issue depending on whether or not the issue goes away in Safe Mode. If the issues you have during normal startup don't show up in safe mode, they are most likely fixed. That means you can reboot normally and your system should be back to normal.
Mac Boot From Usb Key
Step 1: Start your Mac and hold down the Shift key. You will see the Apple logo on your screen.
Step 2: When you see the login screen, you can release the Shift key and login to your Mac.
Step 3: To check whether your Mac has booted into Safe Mode, click on the Apple logo on the top left and then on About this Mac. In the window that opens, click on System Report… You should be able to see this:
How to Fix Mac Won't Boot from USB Drive
Sometimes Mac won't boot from USB as expected. If you are unable to select a different startup disk, it's possible that your disk is not showing up in Startup Manager. If you try Method 1 above but don't see your USB drive listed there, it could mean one of the following problems:
Compatibility: It is possible that the version of macOS or Mac OS X that you have on the USB drive is not compatible with the hardware. That means you won't be able to see it in the Startup Manager so, of course, you won't be able to boot from it. In such cases, you may need to burn a compatible macOS version on USB drive in order to be able to boot Mac from it.
Startup Security Utility: In certain cases where your Mac has the Apple T2 Security Chip (2018 and later devices), it may be your Startup Security Utility settings that are preventing you from booting from USB. In this situation, restart your Mac and hold down the Command + R keys when you see the Apple logo. This will put your Mac into Recovery mode. In macOS Utilities, go to Utilities >Startup Security Utility and sign in as admin. Under External Boot, select the second option - Allow Booting from External Media.
Option ROM Firmware: Another known issue is that Option ROM firmware will not load in Startup Manager until you press certain keys manually. To do this, use Method 1 to access Startup Manager. Once you are there, press Option-Shift-Command-Period. You should now be able to see the USB drive. This is not exactly a problem as much as a feature. If the USB contains Option ROM firmware, you will need to press those keys everytime to boot from your pen drive.
These two methods and the troubleshooting tips should allow you to boot from USB or in Safe Mode so you can then isolate the problem that's preventing your Mac from booting up normally.