Skip to content

Instantly share code, notes, and snippets.

@advixity

advixity/Create a MacOS installer USB (on Windows).md

Last active December 6, 2025 02:28
Show Gist options

  • Select an option

    Learn more about clone URLs
  • Save advixity/16fb1e940ff8469f64cc944844af1375 to your computer and use it in GitHub Desktop.

Select an option

Learn more about clone URLs
Save advixity/16fb1e940ff8469f64cc944844af1375 to your computer and use it in GitHub Desktop.
Download ZIP
A (relatively) simple guide to create a Bootable MacOS installer USB on Windows
Raw
Create a MacOS installer USB (on Windows).md

Create a Bootable MacOS installer USB on Windows

Note! Before proceeding, please make sure that you have a USB flash drive at least 8GB in size. All data will be destroyed on this drive, so please back up your files.

1. Obtaining the image

  • Go to this apple.com support article (10.7 Lion - 10.12 Sierra) and scroll down to "Use a web browser for older versions" Right click your desired OS and click "Save link as". Save the DMG to a folder.

  • Alternatively, go to this archive.org page for all MacOS images and download your version DMG.

2. Preparing the files

  • Using a program such as 7-Zip, open InstallMacOSX.dmg
  • If you don't already have 7-Zip, download it from the link above and run the installer.
  • Navigate to InstallMacOSX.dmg\Install OS X\InstallMacOSX.pkg\InstallMacOSX.pkg\InstallESD.dmg\OS X Install ESD\
  • Extract the BaseSystem.dmg, BaseSystem.chunklist and Packages folder to a folder of your choice
  • Now navigate to InstallMacOSX.dmg\Install OS X\InstallMacOSX.pkg\InstallMacOSX.pkg\InstallESD.dmg\OS X Install ESD\BaseSystem.dmg\OS X Base System\Install OS X El Capitan.app\Contents\Resources\ and extract InstallAssistant.icns
  • Quit the archiver. We won't be using it anymore.
  • In your File Manager (Explorer), rename InstallAssistant.icns to ---> .VolumeIcon.icns

3. Creating the install media

  • Download TransMac (Paid software with Trial) and run the installer.
  • Insert your desired USB flash drive (8GB+) and run TransMac as Administrator (this will give it the neccessary rights to write to the USB drive.
  • Wait 10s! and hit "Run"
  • Select your desired USB flash drive and right-click it. Select Format Disk for Mac
  • Once finished, right click again, and select Restore with Disk Image
  • Select your previously extracted BaseSystem.dmg and hit OK
  • Select Enlarge Volume to Drive Size and press OK
  • Wait a bit for the files to copy over.
  • Select your USB drive in the sidebar of TransMac. There should be a folder called "OS X Base System". Click on the folder.
  • The right window pane should show a folder structure
  • Go back to your File Manager, and locate and select BaseSystem.dmg, BaseSystem.chunklist and .VolumeIcon.icns
  • Drag all 3 files to into the right pane of TransMac. They should begin to copy over.
  • Still in TransMac, navigate to USB-Disk\OS X Base System\System\Installation\
  • Delete the "Packages" File
  • Replace this with the "Packages" Folder that we extracted earlier.
  • Wait for the folder to copy over.
  • That's it! Eject the USB flash drive and unplug it from your computer.

4. Booting and Installing

  • Go over to your Mac. Make sure it is shut down.
  • Plug in the USB flash drive we just created.
  • While holding the Option (Alt) key, power on your Mac. Keep holding the Option key.
  • When you see a menu with your USB flash drive on it, release the key.
  • Select OS X Base System and hit Enter
  • Follow the installation prompts!

5. Uninstalling and Cleaning (Optional)

  • TODO

All credit to: https://www.youtube.com/watch?v=_g8naTAC9jA

@Blender-Uploads
Copy link

Blender-Uploads commented Dec 6, 2025

i got the Ø symbol error after i selected OS X Base System and hitting enter. do i need to follow the video you linked?

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment