Warning: If the DMG file you used was not pre-configured as a bootable volume image, flashing via Etcher will copy the files but might result in a drive that the Mac's startup manager cannot detect. Phase 4: How to Boot Using Your New USB Drive
When prompted to confirm erasing the disk, type Y and press Enter.
Turn on the Mac and immediately press and hold the key. Release the key when you see the boot manager screen. Select the USB installer drive and click Return . On an Apple Silicon (M1/M2/M3) Mac: Shut down the Mac. Plug in the USB installer.
Below is a comprehensive guide to extracting the necessary installer assets from a DMG file and writing them to a USB drive using both the built-in macOS Terminal and a reliable third-party GUI tool. Prerequisites: What You Need Before Starting create mac os x bootable usb installer from dmg
Note: If you changed your USB name in Step 1, replace MyVolume with your drive's actual name.
If your DMG file is a raw byte-for-byte copy of a bootable volume (often designated as a bootable ISO or an uncompressed disk image), you can use BalenaEtcher. Download and run . Click Flash from file and select your DMG file.
Your USB drive must be formatted correctly to be recognized by the Mac's boot system. Connect the USB drive to your Mac. Open (found in /Applications/Utilities/ ). Warning: If the DMG file you used was
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Keep holding the key until the Startup Manager screen appears.
Select the orange drive labeled using the arrow keys, and press Enter . For Apple Silicon Macs (M1/M2/M3 chips): Turn off the Mac completely. Plug in the bootable USB drive. Press and hold the Power button. Release the key when you see the boot manager screen
After conversion, use the dd command with the resulting ISO or IMG file.
is the industry standard for this task. It allows Windows users to open Mac-formatted drives and "restore" DMG images directly to a USB stick. Preparation via Diskpart Before flashing, you must ensure the USB drive uses the GPT (GUID Partition Table)
Either a Mac running macOS or a Windows PC. Method 1: On a Windows PC (Recommended for Dead Macs)
The article needs to be comprehensive. I'll structure it with an introduction explaining why this is useful. Then a prerequisites section covering USB size, identifying the correct DMG, and macOS recovery mode requirements. The core method should use the terminal's dd command for raw DMG writing, as that's the most direct. I'll include warnings about dd being powerful and dangerous.
Once formatted, right-click the USB drive again and select .