Sep 23, 2019 A broken Mac computer with Mac OS X. A trial copy of the TransMac software. One high quality USB flash drive with 16GB of storage. A copy of Apple’s macOS (DMG file). Now that you have all the necessary ingredients, you’re ready to make a Mac OS X bootable USB using the DMG file of the operating system with the steps below. Apr 01, 2020 If your Mac is using a firmware password, you're prompted to enter the password. Option-Command-P-R: Reset NVRAM or PRAM. If your Mac is using a firmware password, it ignores this key combination or starts up from macOS Recovery. Shift (⇧): Start up in safe mode. Disabled when using a firmware password. D: Start up to the Apple Diagnostics. Sep 14, 2015 Bootable optical media (CD or DVD) on Macs equipped with Apple’s Super Drive or a USB thumb drive formatted with a GUID partition type and containing an OS X installer or a usable operating system. Apple advises against booting from external storage containing a version of Mac OS X earlier than the one your Mac shipped with.
I was able to make a macOS Sierra external USB boot disk in a few minutes, and the installation worked without a hitch. Also works with older versions of OS X. Diskmaker X is a popular app. Jun 22, 2013 This option on boot trick works for quite literally any boot volume, whether it’s an external USB drive of any sort, a Thunderbolt hard drive, boot DVD, CD, the Recovery partition, even in dual-boot environments with other versions of OS X, or a Linux or a Windows partition with Boot Camp, if it’s bootable and connected to the Mac it will be visible at this boot manager.
There are various ways to boot macOS. Aside from using the built-in Startup Manager, you can also boot into Verbose, Safe, and Target Disk modes. In addition to this, macOS users also have an option of picking a disk to boot the operating system from. But let’s delve into something more specific. You’re about to find out how to boot your Mac up directly from external storage, specifically flash storage or a USB-based flash drive. Learn how to create bootable flash drive for Windows 10.
Why You Need to Boot from External Drive?
There are many occasions you may have trouble with your Mac.
- Corrupted system files and Mac crashes unexpectedly.
- Mac runs very slow with sufficient storage.
- You have deleted some system files wrongly.
- You couldn’t login to your Mac.
- Troubleshooting purposes.
Let’s begin with the obvious question here; what are the basic requirements for creating bootable USB for Mac?
How to Create Bootable USB Drive for Mac?
- USB drive with sufficient storage space.
- Access to a working and supported Mac.
- Format USB to Apple supported file system.
- Get installer file for macOS.
- Create bootable USB.
- Booting Mac from Startup Manager.
If you are not able to login to your Mac, you need to use Time Machine backup disk. Otherwise you should have another Mac for creating a bootable USB.
1. USB Drive
The macOS installer file is large with approximate size of 6 to 10GB depending upon the version. Also the process needs to sufficient storage space on your USB. So ensure to have at least 32GB or greater storage space on your USB drive.
Remember to copy and backup the USB since you need to delete the entire content for creating the bootable drive.
2. An Intel Based Mac
Apple transitioned to an Intel processors in 2005. In other words, if your Mac is not older than 2005, you should be fine.
3. Format USB Flash Drive to Apple File System
First, plug in your USB drive. Press “Command +Spacebar” to access Spotlight, then type “Disk Utility”. You can view the current file system of the USB drive. In our example, we have FAT32 file system which is compatible on Windows. You need to erase and format the USB to be compatible with your Mac.
Click on the “Erase” button on “Disk Utility” and choose the format as either APFS or Mac OS Extended. In most cases, your Mac will show the supported format by default and you don’t need to change it. On older Mac, you will see an additional scheme option, choose “GUID Partition Map”. Click on “Erase” button to continue further.
Disk Utility will delete all content on the USB and format it in the selected APFS or Mac OS Extended format.
4. MacOS Installer File
In order to create a bootable USB drive for Mac, you need download Mac OS installer. Open App Store on your Mac and search for the latest macOS version. Remember, App Store will only have the latest version which is macOS Mojave at this point when we write this article. Search for “macOS mojave” and click on the “Get” button.
This will start downloading the installer file to your “Applications” folder.
5. Creating USB Installer
After downloading, the installer will automatically ask you to install macOS Mojave. Simply quit the installer without starting the installation.
- At this point, ensure you have inserted the formatted USB drive, let’s say the name of the USB volume is “Boot Disk”.
- Also make sure the downloaded macOS installer file is in “Applications” folder.
- Press “Command + Spacebar” and search for “terminal” to open Terminal app.
- Copy and paste the below command in Terminal and hit enter.
- You need to enter admin password to proceed further.
- Terminal will ask you to confirm erasing the volume, press Y and hit enter to confirm.
Ready to start.
To continue we need to erase the volume at /Volumes/Boot Disk.
If you wish to continue type (Y) then press return:
- Now the erase disk process will start to copy the installer file on the USB drive. After successful completion of the process, name of the USB drive will be changed similar to the installer file name like “Install macOS Mojave”.
Note that Apple discourages booting with an earlier macOS version than the version your device is shipped with.
6. Boot Mac from USB
Follow the below process to boot your Mac from bootable USB:
- Insert the bootable USB installer drive and go to “Apple Menu > Restart”.
- When your Mac restarts, press and hold the Option key till “Startup Manager” opens.
- The Startup Manager scans and lists the drives that are connected and bootable.
- Note that the Startup Manager will only list volumes that include bootable volumes. If you only see “Macintosh HD” like below then the USB drive is not connected to your Mac or not created properly with the installer file.
- Select your Wi-Fi network name from the “Choose Network…” dropdown and enter the password to connect to internet. Remember, you need to have an internet connection for installing from USB as the installer needs to get updates for your Mac from Apple’s server.
- Double click on your USB that contains the macOS installer or highlight it and press the return key.
- You will see macOS Recovery app and choose “Install macOS” option from Utilities.
- It may take long time depending upon your Mac to start booting with macOS Mojave.
Wrapping Up
As simple as the process seems, it tells you a lot about your system. For example, if a USB flash drive that contains a bootable copy of macOS doesn’t show up on the Startup manager, you may need to repair the disk permission. Also, remember to format the USB drive with a APFS or Mac OS Extended format.
That said, now you know how to boot up another version of or a copy of macOS and troubleshoot possible issues with your device.
If your Mac suddenly refuses to boot up properly, you might need bootable macOS install USB to make repairs. But how do you create such a disk if all you're left with is a Windows 10 computer? Fortunately, there's a great tool that you can use for free to create bootable macOS media on a USB drive in a Windows 10 environment. This article shows you how to download a macOS DMG file, format a USB drive using a GUID Partition Table, burn the DMG to the drive and boot your Mac from the USB. All the steps except the last one are done on a Windows 10 machine.
Part 1: Download macOS or Mac OS X DMG File
The first step is to get the DMG disk image file for the version of macOS that you want. You can get a copy of the latest macOS version from Apple download portal or App Store here. There are also several other direct download sites that offer various versions of Mac OS X in DMG format rather than the standard APP format that runs on Mac. Since you're working in a Windows environment, you need the DMG rather than the APP file.
Part 2: Format USB Drive to GPT
Mostly, the USB drive was formmated to FAT32 in default when being shipped out from the factory. However, FAT32 can be only used for installing OS with legacy BISO, which doesn't work for macOS. So the next step is to format your USB drive in the GPT partition style in order to burn installation files to the desired USB drive. You can do this in Command Prompt as admin. In elevated Command Prompt (Ctrl+Shift+Enter), input the following series of commands followed by Enter after each line:
Diskpart
List disk
Select Disk X (X stands for the USB drive name that appears after the previous command)
Clean
Convert GPT
Create partition primary
Part 3: Create Bootable macOS USB from Windows 10
You have now formatted the partition of USB drive. It's time to download UUByte DMG Editor for Windows. Although this is a premium software, you can use the initial free trial period to create a bootable macOS USB drive on Windows 10. After installing the application, follow the sequence of steps shown below:
Mac Os X Boot From External Usb Drive
Step 1: Right-click the software icon on desktop and select 'Run as Administrator' from the contextual menu. Choose 'Run' when prompted.
Step 2: Insert your formatted USB drive, and click 'Burn' ta on the main screen.
Step 3: Click 'Browse' button to import macOS dmg file into the program. And select the USB drive name from the second row. You can also set a volume labe for that USB drive.
Step 4: Click 'Burn' button at the bottom to start the process. You will see a progress bar and wait around 10 minutes to get it done.
Step 5: Once the progress bar is at 100%, a bootable macOS USB is ready. After that, you can use that USB drive for installing macOS.
This is one of the easiest way to create a bootable macOS USB on a Windows PC. The steps are simple and instructions are pretty clear.
Part 4: Boot macOS Install USB on Mac
Now remove the USB drive and insert it into the Mac computer. To boot from the disk, you need to hold down the option key when you hear the boot chime. This will take you to the Startup Disk Manager, where you should be able to see the USB drive. It might have a different name, but as long as it is bootable, you'll be able to see it there. Once you select it, the computer will boot from the disk and the macOS installation will begin.
Conclusion:
Boot From Usb Drive Windows 10
The whole process might look a bit complicated if this is your first time, but just follow the instructions in this article and you should be fine. That being said, you need to be careful when downloading the DMG file and formatting your USB drive. If you don't do these two steps correctly, the output drive from the UUByte DMG Editor software won't be bootable, which means you can't install macOS using it, and you may need to do the whole thing over again.