Download MacOS Catalina DMG File; Partition USB Disk on Windows using CMD. Connect your USB. Go to the start menu and run CMD as an administrator. Then, type List Disk.; Afterward, type Select Disk 1 and press enter key.; Now, type Clean to format USB drive and press enter key. After that, you need to create a partition, therefore, type Create partition primary and press enter key. Create a macOS Catalina USB Installer Using Disk Creator One of the easiest ways to create a bootable installer for any macOS update, including Catalina, is to use the Disk Creator app. It’s a simple program that allows you to load your update and then create an installer based on that update.
If your computer runs Windows 10, it's a good idea to have a bootable Windows installation disk, in case you ever want to reinstall Windows on your computer.
If you don't have a Windows 10 disk, you can create one using the methods described below.
Method 2: Download ISO and create bootable USB.
Requirements
Before you create a bootable Windows 10 disk, make sure you have the following:
A computer connected to the Internet, with a USB port or DVD burner.
A USB flash drive with a capacity of at least 8 GB, which is either empty or ready to be completely erased; or a blank DVD-R disk.
A valid Windows 10 license; either a numeric license key or a Microsoft account with a Windows 10 license that is associated with your computer.
Method 1: Use the Media Creation Tool
The Media Creation Tool is a program provided by Microsoft that downloads all required files, and write them to your DVD or USB flash drive. Follow these instructions to download and use the Media Creation Tool.
Warning
The following steps will completely overwrite the data on your USB flash drive. All existing data on the disk will be destroyed.
Open a web browser and go to Microsoft's Windows 10 download page. Under Create Windows 10 installation media, click Download tool now.
Run the installer. At the UAC prompt, click Yes. The installer gets things ready, then displays Notices and License terms. Read the terms and click Accept to proceed.
At the screen What do you want to do?, select Create installation media for another PC, and click Next.
At Select language, architecture, and edition, don't change anything if you're creating the installer for this computer. Make sure Use the recommended settings for this PC remains checked. (If you're creating a disk for another computer, uncheck this box and make changes now.) To continue, click Next.
At the screen Choose which media to use, you can choose USB or DVD as the destination. In this example, we'll create a USB flash drive. Select USB flash drive, and click Next.
You'll be asked to Select a USB flash drive. If your USB flash drive is not inserted, insert it now, wait a few moments and click Refresh drive list.
Then, select your USB flash drive, and click Next.
Windows 10 downloads the installer and write it to your USB flash drive. You can continue using your PC while it runs in the background.
When it's finished, you'll see Your USB flash drive is ready. Click Finish. Setup will clean up its temporary files and exit automatically.
You can now remove your USB flash drive from the computer. For information about how to use it, see how to boot with your installation disk, below.
Method 2: Download ISO and create bootable USB
You also have the option to download the Windows 10 ISO image file to your computer, then create your bootable disk manually with another program.
If you're using Windows, you must use the Media Creation Tool to download the ISO. If you're using another operating system, such as macOS or Linux, Microsoft offers a direct download.
Windows: Download ISO with Media Creation Tool
If you're using Windows, follow these steps to download the Windows 10 ISO with the Media Creation Tool. (Steps 1–4 are the same as in method 1.)
Open a web browser and go to Microsoft's Windows 10 download page. Click Download tool now.
Run the installer. At the UAC prompt, click Yes. Read the license terms and click Accept.
Select Create installation media for another PC, and click Next.
At Select language, architecture, and edition, don't change anything if you're creating the installer for this computer. Click Next.
At Choose which media to use, select ISO file, and click Next.
Choose a location on your computer to download the ISO file, such as your Downloads folder. Make sure you have enough space to download the file (it's big - between 3 and 5 gigabytes, depending on the version).
When the download is complete, Media Creation Tool offers to Burn the ISO to a DVD. It also displays the full path and file name of the ISO file on your computer.
Optional: If you'd like to verify the location of the file, click the file name to open the folder where it was downloaded.
Optional: If you'd like to burn a DVD of the ISO now, click Open DVD Burner to open the Windows Disk Image Burner. Insert a blank DVD-R disk into your DVD drive and follow the instructions.
Click Finish to close the Media Creation Tool.
You can now skip to the step create bootable USB with Rufus.
macOS X, Linux: Download ISO directly
If you're using a non-Windows operating system, follow these instructions to download the Windows 10 ISO.
Open a web browser and go to the Windows 10 ISO download site. Microsoft detects your operating system and reroute you to the direct download page.
Under Select edition, select Windows 10 and click Confirm.
Under Select the product language, select your language (English, for example), and click Confirm.
Under Downloads, you'll have the option to download the 32-bit or 64-bit version of Windows. If your computer has a 64-bit CPU, choose the 64-bit Download. If you're not sure, see: How to determine if you have a 32-bit or 64-bit CPU.
The download begins in your browser. Make sure you have enough disk space to download the file (it's big - between 3 and 5 gigabytes, depending on the version).
Create bootable USB with Rufus
Now that you've downloaded the ISO file, you need special software to create a bootable USB flash drive with it. Only copying the file to the USB will not work.
There are various programs which you can use to create a bootable USB flash drive in Windows, such as UNetbootin. In these instructions, we'll use a free Windows program called Rufus.
Warning
The following steps will completely overwrite the data on your USB flash drive. All existing data the USB flash drive will be destroyed.
Open a web browser and go to the Rufus website. Scroll down to Download, and choose either Rufus or Rufus portable (either one works).
When the download is complete, run the Rufus executable. You don't need to install it because the program runs without being installed.
If your USB flash drive is not inserted, insert it now. It will be immediately recognized by Rufus.
Click the disk icon. It looks like an optical drive and disk. Navigate to the Windows ISO you downloaded, select the ISO file, and click Open.
The Rufus status line will say 'READY.' To write the ISO to your USB flash drive, click Start.
Rufus warns you that all data on the USB will be destroyed. If you have any important files on the USB flash drive, this is your last chance to cancel, and back up your files. To proceed, click OK.
The ISO is written to the USB flash drive. It should only take a few minutes.
You'll know it's complete when the progress bar is fully green, and the status line says 'READY' again.
Click Close to exit Rufus.
How to boot with your installation disk
To use your Windows 10 installation disk, follow these steps.
Verify the computer's BIOS is configured to boot from a removable disk. To access your BIOS, you need to reboot the computer and press a specific key before boot sequence begins. For detailed instructions, see: How to enter the BIOS or CMOS setup.
Then, if necessary, change your boot sequence so the DVD/USB drive is listed before your HDD or SSD in your boot order. (If you don't see your USB drive in the list, insert your installation USB flash drive before powering on the computer and try again.)
If your BIOS is properly configured, power down the computer.
Insert your installation disk.
Power on the computer.
Instead of loading the operating system from your HDD/SSD, your computer boots from your removable disk, and the Windows installation begins.
Additional information
Jun 08, 2020 • Filed to: Solve Mac Problems • Proven solutions
Creating a bootable drive for your Mac certainly seems to be a wise decision to make. Even though MacOS recovery partition can take care of all your recovery requirements in times of need, it’s still worthwhile to have a bootable installer.
Why Do You Need to Create A Bootable Drive For Your Mac?
The Mac installer gets deleted as soon as you download it and use it by installing the Mac operating system. Once the installer gets deleted, it means that you can no longer use it to install the MacOS on another Mac device. You will have to again download the installer on the latter Mac to install the MacOS. This can take a lot of time and become inefficient if you have multiple Macs.
Clean installs can be performed by installers which are very helpful in overwriting your start-up drive. You can also use this function for other troubleshooting issues as well.
When you have a bootable installer, it ensures that you are well guarded in an emergency scenario by making use of some of its helpful utilities.
A bootable installer can allow you to install an earlier version of MacOS and also let you temporarily boot into the previous version of the MacOS.
What Do You Need Before Creating Your Bootable Drive?
Before you begin the process, you will need the following:
USB Stick / External Hard Drive: If you are planning to use a USB for downloading the bootable version of the installer, make sure that it is 8GB in size or larger than that. In the case of Sierra, 12GB is recommended as the minimum requirement. Ideally, 32GB to 64GB is a good size to have as it is not only cost-effective but also gives a better performance. In the case of an external drive, you can use any spare one that you are not going to use for any other work.
Download MacOS High Sierra Installer: It is important to note that once you have downloaded the installer, it will begin with the installation process on its own. You can close the installer just like you quit any Mac app. In the case of the macOS version being older than the current one, you can click on ‘ok’ once the message flashes that the version is too old to install. You can find the old installer file in your ‘Application Folder’. Don’t forget to take a backup of your Mac to be on a safe side.
Part 1. How to Create a Bootable Drive Using Terminal
There are two ways of creating a bootable copy of the installer. You can either use Terminal or get the job done through a free software like Recoverit to do it for you. First, let us look at how to create a bootable drive using Terminal.
Steps to create a MacOS Siera beta boot disk:
The first step in the process is to connect your external hard drive to your Mac. You need to name your external drive ‘untitled’ for the Terminal command to work.
Launch Terminal. You can find this in the 'Utilities' folder of your Applications folder.
In this step, you have to paste the copied instruction on the screen by going back to the Terminal.
You will be required to feed in your user password now and then hit ‘Return’.
Now, the Terminal will ask for your permission to erase the drive. To continue, type ‘Y’ and again hit return.
After the Terminal has erased your drive, your Mac will prompt you if you wish to use the drive for Time Machine. Click ‘Don’t Use’.
Next, the installer file will be copied by the Terminal to your drive. This might take some time, so be patient.
Once the copying is completed, a ‘Copy complete’ message will be displayed on your screen. You can now quit the Terminal and use your drive.
Part 2. How to Create Bootable Media for Mac with Recoverit Mac Data Recovery
Recoverit Mac data recovery software is one of the most impressive and easy-to-use data recovery software in the market, and it has lots to offer with its varied utilities and functions. With Recoverit to create bootable media, you can access your system easily without the need to reinstall the MacOS to recover your lost data.
Step 1 Launch Recoverit and get to select 'Computer Crash Recovery'. Click 'Start'.
Step 2 Choose your connected external hard drive as the bootable media, and click 'Start'. You will receive a requirement of formatting the device. Before the formatting, remember to back your drive data up.
Macos Boot Camp Drivers
Step 3 Wait for a while, and Recoverit will format your drive and start creating the bootable media.
Step 4 Once it finishes, follow the next steps to restore data back.
Part 3. How to Set the Computer Boot from the Bootable Media
Step 1 Connect your external drive to your unbootable Mac.
Step 2 Press down on the ‘Option’ key after restarting your Mac.
Create Usb Boot Disk For Macos High Sierra
Step 3 Once the booting has finished, your Mac will display the Startup Manager to show you the available boot drives. Select your external hard drive and hit ‘Return’.
Creating A Boot Disk For Mac Os X
Step 4 If you want to install Sierra but keep your data untouched, you can select 'Install OS X'. However, if you wish to delete all your data, then you can select Disk Utility to format the entire drive and wipe away all your data to reformat the internal drive first and then install MacOS Sierra.
Boot Macos Into Recovery
You now have a bootable copy of the MacOS Sierra installer, and you can use it on multiple Macs to install the Mac OS. If you are familiar with the command line, you can opt to create a bootable drive using Terminal. For others, you can simply opt for reliable Mac hard drive recovery software like Recoverit and assist you in recovering your data as well from crashed systems in case of emergencies.