Example: I had bootable USB installer with Big Sur 11.2.2. Inside of that partition is just 'Install Mac OS Big Sur' app. I downloaded 11.4 pkg from Apple Servers, installed it in Applications folder and simply moved the app to the same external USB (after deleting 11.2.2 first from there) It booted from Recovery and installed 11.4 from scratch. Bootable USB Installers for OS X Mavericks, Yosemite, El Capitan, and Sierra. First, review this introductory article: Create a bootable installer for macOS. Second, see this How To outline for creating a bootable El Capitan installer. Simply replace the Terminal command with the one from the preceding article by copying it into the Terminal. Choose your USB flash drive and let Disk Drill make it bootable for you. Method 2: Run “createinstallmedia” in Terminal. Assuming you’ve downloaded the macOS Monterey installer, you can go ahead and run the “createinstallmedia” command in Terminal to create a bootable USB drive: Connect a suitable USB drive to your Mac.
Matt Cone January 17, 2013 TutorialsMac
It’s a good idea to have a bootable emergency drive on hand, just in case disaster strikes your Mac. An emergency drive (also referred to as an OS X Recovery Disk) can help you repair the hard disk, reinstall the operating system, and restore from a Time Machine backup to get your computer back fast.
With previous versions of OS X, you could have used the installation DVD to fix problems. But OS X Mountain Lion is sold in the App Store as a digital download — no physical disk is provided. What’s a maintenance-minded Mac user to do?
Create your own bootable OS X USB drive, of course! It’s easy, and if you’ve already purchased OS X and have a USB drive that’s 1 GB or larger, it’s completely free. Carry it in your pocket or put it on your keychain so it’s available if the worst-case scenario occurs. You’ll thank yourself for taking the time to complete this project.
Evaluating Your Emergency Drive Options
It can happen to any of us, even those who own brand-new Macs. First your computer starts freezing infrequently, then crashing more often, and then it won’t start at all. For situations like this, you need an emergency drive on hand to start up your computer and troubleshoot the problem.
Emergency USB Drive: Creating a bootable USB drive is your safest bet. This device is self-contained and kept entirely separate from your computer — and any potential problems associated with it. But if you don’t want to create a USB drive, you may have access to two other types of emergency drives, depending on when you purchased your Mac.
Recovery HD: Every Mac running OS X Lion and later has a hidden Recovery HD partition that can be used to boot the computer and repair the hard disk. (To use the Recovery HD partition as your startup disk, hold down Command-R at startup or, if that doesn’t work, option.) But the Recovery HD probably won’t work if the internal hard drive is damaged. When you can’t boot from the regular startup disk, chances are you won’t be able to boot from the Recovery HD either.
Internet Recovery: Macs purchased after OS X Lion was released have an additional feature called Internet Recovery, which works even if your internal hard drive is damaged. If there’s a problem with your computer, it can network-boot from Apple’s servers. First, your computer’s memory and hard drive are checked for major issues. If none are found, your Mac downloads and boots from a Recovery HD image. But even if your Mac has this feature, you’ll still benefit from having an emergency drive, as it can take a while to download the Recovery HD partition.
Purchasing a USB Drive for Your OS X Recovery Disk
If you don’t have a spare USB drive, you’ll need to purchase one. We recommend the Amazon Basics 8 GB USB Flash Drive, which is a simple and affordable option available for less than $10.
Making Your Own Emergency OS X USB Drive
The best option is a Recovery HD partition on a bootable USB drive. This drive provides you with all the tools you need to troubleshoot problems, repair the hard drive, reinstall OS X, and restore from a Time Machine backup. In short, it’s the perfect safety net for those rare times when your internal hard drive is hosed.
Here’s how to create an emergency USB drive:
Connect a hard drive or USB drive to your computer. If the drive is larger than 1 GB, consider partitioning it to make a 1 GB partition for the recovery disk. (If you don’t create a partition, this process will use all of the available space on the drive, no matter how large it is.)
Open the Recovery Disk Assistant application. It’s available for free from Apple’s website.
Accept the license agreement. The Recovery Disk Assistant window appears, as shown below.
Select the disk and then click Continue.
Authenticate with your administrator username and password. The Recovery Disk Assistant creates the recovery disk, as shown below. The process takes approximately five minutes.
When the recovery disk has been created, click Quit.
Like the Recovery HD partition on your startup drive, the emergency drive is invisible when it’s connected to your computer. The Finder won’t provide any indication that it exists, but don’t worry — it’s there, waiting for your signal to help with a disaster!
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Most new PCs don't come with DVD drives anymore. So it can be a pain to install Windows on a new computer.
Luckily, Microsoft makes a tool that you can use to install Windows from a USB storage drive (or 'thumbdrive' as they are often called).
But what if you don't have a second PC for setting up that USB storage drive in the first place?
In this tutorial we'll show you how you can set this up from a Mac.
You can download the ISO file straight from Windows. That's right - everything we're going to do here is 100% legal and sanctioned by Microsoft.
If you want an English-language version of the latest update of Windows 10, you can download the ISO here.
If you have a relatively new computer, you probably want the 64-bit version. If you're not sure, go with the 32-bit version to be safe.
If you want a non-English-language version of Windows, or want to get an older update version, download the ISO here instead.
The ISO file is only about 5 gigabytes, but I recommend you use a USB drive with at least 16 gigabytes of space just in case Windows needs more space during the installation process.
I bought a 32 gigabyte USB drive at Walmart for only $3, so this shouldn't be very expensive.
Stick your USB drive into your Mac. Then open your terminal. You can do this using MacOS Spotlight by pressing both the ⌘ and Space bar at the same time, then typing 'terminal' and hitting enter.
Don't be intimidated by the command line interface. I'm going to tell you exactly which commands to enter.
Open Mac Spotlight using the ⌘ + space keyboard shortcut. Then type the word 'terminal' and select Terminal from the dropdown list.
Paste the following command into your terminal and hit enter:
You will see output like this (note - your Mac's terminal may be black text on a white background if you haven't customized it).
Copy the text I point to here. It will probably be something like
Next format your USB drive to Windows FAT32 format. This is a format that Windows 10 will recognize.
Note that you should replace the
disk2 with the name of the your drive from step 3 if it wasn't
disk2. (It may be
Run this command using the correct disk number for your USB:
diskutil eraseDisk MS-DOS 'WIN10' GPT /dev/disk2
Then you'll see terminal output like this.
This will probably only take about 20 seconds on a newer computer, but may take longer on an older computer.
Note that for some hardware, you may instead need to run this command, which uses the MBR format for partitioning instead of GPT. Come back and try this command if step 7 fails, then redo steps 5, 6, and 7:
Now we're going to prep our downloaded ISO file so we can copy it over to our USB drive.
You will need to check where your downloaded Windows 10 ISO file is and use that. But your file is probably located in your
~/Downloads folder with a name of
hdiutil mount ~/Downloads/Win10_1903_V1_English_x64.iso
Update April 2020: One of the files in the Windows 10 ISO – install.wim – is now too large to copy over to a FAT-32 formatted USB drive. So I'll show you how to copy it over separately.
Thank you to @alexlubbock for coming up with this workaround.
First run this command to copy over everything but that file:
rsync -vha --exclude=sources/install.wim /Volumes/CCCOMA_X64FRE_EN-US_DV9/* /Volumes/WIN10
Then run this command to install Homebrew (if you don't have it installed on your Mac yet):
/usr/bin/ruby -e '$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)'
Then use Homebrew to install a tool called wimlib with this terminal command:
brew install wimlib
Then go ahead and create the directory that you're going to write the files into:
Then run this command. Note that this process may take several hours, you may see 0% progress until it finishes. Don't abort it. It will use wimlib to split the install.wim file into 2 files less than 4 GB each (I use 3.8 GB in the following command), then copy them over to your USB:
wimlib-imagex split /Volumes/CCCOMA_X64FRE_EN-US_DV9/sources/install.wim /Volumes/WIN10/sources/install.swm 3800
Once that's done, you can eject your USB from your Mac inside Finder. Note that Windows will automatically rejoin these files later when you're installing.
How To Create Bootable Usb In Mac
Congratulations - your computer now should boot directly from your USB drive. If it doesn't, you may need to check your new PC's BIOS and change the boot order to boot from your USB drive.
Windows will pop up a screen and start the installation process.
Create Bootable Usb From Iso
Enjoy your new PC, and your newly-installed copy of Windows.