Set the default startup disk You can change the startup disk your Mac automatically uses from System Preferences. From the Apple menu choose System Preferences. Click the Startup Disk icon in System Preferences, or choose View Startup Disk. Here is a guide on how to create a bootable external Mac hard drive to run macOS from an external hard drive. There are quite a few reasons for why you may want to be able to have an additional startup drive for your Mac. One of the main reasons is backup of your current system. Another is creating a drive for testing your Mac’s hardware.
If you’re still using a Mac OS X the time will come when your computer won’t boot, or a problem may arise where you can’t take control of the device, and booting from an OS X installation media will be required.
This is why it’s recommended that you make a Mac OS X bootable USB when your Mac is in working conditions. However, if you find yourself on a scenario where your device (iMac, MacBook Pro, Air, Mac Pro or Mini) is not responding and you happen to have a Windows 10 device, then you can still be able to make a USB bootable installation media for your Mac OS X to reinstall the operating system using the Recovery Assistant.
These instructions will also work for Windows users who are running Mac OS X on a virtual machine and need to upgrade to the latest version. For instance, to OS X Yosemite.
Before you dive into this guide, you’ll need a few things:
- 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.
Create Mac OS X bootable USB installation media
Before you can use TransMac, you first need to partition your USB flash drive with a GPT partition, as a normal MBR partition may not work. To do this, you’ll need to use the Diskpart command-line utility on Windows 10.
Setting up GPT partition
- Select your boot drive as the source for the clone. Set your USB drive as the target for the cloning operation. Click “Clone” to start the cloning process. The content of the USB drive will be overwritten and replaced with the clone of the boot drive. Booting from a USB Drive.
- Launch Disk utility and connect a USB drive to the Mac Select the USB drive from the left menu and click on “Erase” tab, choose “Mac OS X Extended (Journaled)” as the format, then click on the “Erase” button in the corner Now select the formatted USB drive from the left side and click on the “Restore” tab.
Use these steps to set up a USB drive with a GPT partition:
Open Start on Windows 10.
Search for Command Prompt, right-click the top result and select the Run as Administrator option.
Type the following command to open Diskpart and press Enter:
Type the following command to determine the USB flash drive and press Enter:
Type the following command to select the storage and press Enter:Quick tip: The
select disk 1command as an example, but you have to replace 1 with the number of the flash drive you want to use.
Type the following commands to delete everything from the USB thumb drive and press Enter:
Type the following command to convert the drive into a GPT partition and press Enter:
Type the following command to select the new partition and press Enter:
After you complete the steps, the USB flash drive from MBR to GPT format, you can use the steps below to create a bootable USB installation media to install Mac OS X.
Create USB install media
Use these steps to create a bootable media to install Mac OS X:
Download and install a copy of TransMac.Quick note: TransMac is a paid software, but it has a 15-day trial solution, that give us more than enough time to move the DMG files to the USB drive from Windows. (If you want to support the developer, you can purchase the full version.)
Insert the USB drive that you’ll use to fix your installation of OS X. (Remember that all the data in the USB will be erased. Make sure you take off any important documents.)
Right-click the TransMac software icon and Run as administrator. (You’ll be prompted to Enter Key or Run, because we’ll be using it once, click the Run option.)
On the left pane, you’ll see all the Windows PC drives listed, right-click the USB drive that you’re intending to use to reinstall Apple’s OS X and select the Restore with Disk Image option.
In the warning dialog box, click the Yes button.
Use the Restore Disk Image to Drive dialog box to browse for the DMG file with the installation files for Mac OS X Yosemite in this case, and click the OK button to create a bootable USB of the operating system.
Now, you’ll have to wait a long time. No kidding. It could take one or two hours to complete the process depending on your computer and other variables.
Once your bootable USB installation media is ready, remove it and insert it into your Mac, power it on, holding down the Option key, and select the USB you just created to reinstall Mac OS X.
If you’re having issues trying to create a bootable media, you can get a USB flash drive that comes with Mac OSX ready to install.
Dec 16, 2020 • Filed to: Solve Mac Problems • Proven solutions
Make External Hard Drive Bootable Mac
A Universal Serial Bus or USB Drive, also known as a flash drive is a portable data storage device that includes a memory which includes a USB interface. It is typically removable and much smaller than an optical disc. Any sort of data can be stored in this device. The drives are available in various sizes and as of to date, the 2TB(Tera-Byte) flash drives in terms of storage capacity are the largest ones available in the market.
Today, these drives are one of the most consumed used devices in the world. Thanks to their portable nature, affordability, and compatibility, USB drives are being used to send and receive endless information across a surplus of networks and platforms all around the globe. This small tool has opened the world to a stream of limitless options with respect to storing, transferring, copying data, and much more. One of them includes Booting the Mac from such a device.
Part 1. Reasons for Mac Boot from USB
Booting the Mac from USB in a way gives the power back to the user. The likeliest of the reason for choosing the boot from the USB method is that your Mac won't start which denies the user access to the computer. Using an external source like the USB drive helps the user get around the problem. It provides the user access to the contents of the internal drive, assuming the data is safe and not corrupted. It also helps to repair the Mac disk with Disk Utility and other tools. Here are the top reasons why the user should choose to Boot Mac from USB:
- Allows the user to install a different version of macOS.
- It allows the user to test a new version before you make the decision to upgrade.
- Allows risk-free testing of the Beta version.
- Faster and efficient.
- By installing older versions through USB, it permits certain Apps to run which are not compatible with the latest macOS.
Part 2. Preparations for Booting Mac from USB
To ensure a risk-free procedure certain measure should be taken:
- The user should buy a name-brand flash drive.
- The USB should contain 16-32GB of free space.
- The user should scan the flash drive with some reputable Anti-Virus software.
- The user should check to see what size of ports they have on the Mac. A 12' Mac only contains a single C-Type port.
- Make sure to purchase the C port flash drive to avoid any inconvenience.
- It is advised that the user should go with a USB 3.0 supported drive, with a size of 16GB to ensure a swift transfer of data.
- The USB drive should be formatted with a supported GUID partition.
- It should contain an OS X installer or a usable operating system to work with.
Part 3. How to Create Bootable USB on Mac
Make External Drive Bootable Mac
There are a few general guidelines that can help get your machine started which are mentioned above, regardless of the OS the user prefers. Here are the methods to create a bootable USB drive on Mac.
Creating a Bootable USB Using Terminal
The terminal is the default gateway to the command line on a Mac. It is just like the Command Prompt feature works for MS Windows. The Terminal feature ensures a hassle-free experience for the Mac user without the conventional pointing and clicking, the user just has to type the commands and the computer does the rest. The user can find Terminal in the Applications > Utility folder or it can be checked in the finder utility.
Using the Terminal feature is the most simple way to create the bootable USB drive. The user just needs to follow one easy step which is renaming the MyVolume portion of the command with the name of the drive. The name of the drive can be changed using the Disk Utility of Mac. Here are the steps required after opening the Terminal feature to create a bootable USB drive.
- Copy and paste the command which is suited for the version of the operating system into the Terminal window.
- The command for MacOS Mojave is as follows:
- Press the Return key.
- Enter the password.
- Confirm to erase the USB drive by typing Y followed by the Return key.
- The terminal will erase all the data inside the drive and create the bootable USB drive.
If there is a need to install a different version of the operating system then the user just has to replace the above-underlined command with their desired version of OS. For example, if the user wants to install Mac OS Sierra instead of Mojave then they would have to replace 'Mojave.app' with 'Sierra.app' inside the command line.
Part 4. How to Boot Mac from USB Media
After creating a bootable USB drive, the user simply needs to plug the created drive into the open port on the Mac. Here are the steps to boot Mac from the USB flash drive:
- Power on the system.
- Press and hold the Option (Alt) key on the keyboard when the computer starts.
- Select the USB drive as a startup disk when the option appears.
- The system will start the boot process off the USB drive.
- Install the operating system from the macOS utilities.
- Data can be restored by using the Time-Machine backup option.
Video Tutorial on How to Boot Mac into Recovery Mode
Part 5. How to Recover Data from Unbootable Mac
The Mac becomes unbootable when the BIOS which is a firmware that is used to perform hardware initialization during the booting process fails to recognize the startup process. It usually happens when there is a failed system update, system crash, damaged MBR, or when the drive becomes corrupt.
Recoverit Mac Data Recovery software is the most efficient option to recover all the lost data when Mac becomes unbootable. Developed by Wondershare, Recoverit is one of the most preferred recovery tools in the world. The tool provides an instant preview of what is recovered after a detailed scan. It allows us to connect almost every type of portable device and recover data from them. Data can be restored by performing the recovery and repair process. The process involves the installation of the Recoverit software that offers users the chance to get back the important data that they had lost.
Step 1. Create a Bootable Media
To recover data from an unbootable Mac, you need to create a bootable media first.
- Installation: Please Install Recoverit by clicking on the icon.
- Select an option: For your crashed Mac, please choose the 'Computer Crash Recovery' option.
- Initiate Recovery Process: Click on 'Start' for the recovery process to launch.
- Create Bootable Drive: Select the 'Create USB bootable drive' option and click on 'Create'.
- A pop-up dialogue will appear that will prompt the user to format the USB drive.
- Format the Drive: Click on 'Format' Now.
- Recoverit will show you the process of formatting the USB drive and creating a bootable drive.
- After a while, the bootable drive will be built up. And please follow the guides which Recoverit shows you.
Step 2. Recover Data from Crashed Mac
Here are the following steps required to recover data from an unbootable computer.
1. Select the Location
When you launch Recoverit, you can select a location to scan. In this case, we will be performing data recovery on Mac's internal hard drive (Macintosh HD) instead of any other connected source.
2. Scan the Location
As soon as you would click on the 'Start' button, Recoverit will take the needed steps for data extraction. If you want positive results, then try not to close the application in between.
3. Preview and Recover
When the data recovery process is completed, the application will display the results on the interface. You can go to any category of your choice from here and preview the retrieved content. Make the needed selection and click on the 'Recover' button to save your files to a secure location.
All hope gets lost when the computer becomes unbootable and the data gets deleted. Recoverit recovery software is the most convenient program when it comes to retrieving lost data from the computer.
Installing the macOS from a USB flash drive gives the user an instant solution when the Mac installer due to some reason refused to work. The method to create a bootable drive is easier than it sounds. Now, you know what to do whenever you want to upgrade your macOS from a bootable external source by following different methods to ensure a safe and hassle-free process. If you lose valuable data when the Mac becomes unbootable then you can easily recover the lost files by using the Recoverit recovery software. Recoverit guarantees data recovery in no time.
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