If your Mac is out-of-order or you otherwise cannot download macOS from the App Store, you can still create a bootable OS X recovery USB, and you can use that to create an Installer USB.
The downloads used in this process are legal and freely avaliable - including disk images directly from Apple's IT support pages, and open source utilities for extracting and converting pkg, dmg, and HFS+.
No hackery. No hackintosh-ery.
This process works for
- macOS Catalina (10.15)
- macOS Mojave (10.14)
- macOS High Sierra (10.13)
- macOS Sierra (10.12)
- OS X El Capitan (10.11)
- OS X Yosemite (10.11)
In all cases you should first download the El Capitan Installer, as a direct download from Apple (no App Store).
The OS X Yosemite and macOS Sierra images should also work, but you might have trouble getting macOS Sierra to boot in VirtualBox.
This is a 3-step process:
- Create a Recovery ISO with Linux
- Create an El Capitan Installer ISO with VirtualBox from the Recovery image
- Create other Installer USBs from El Capitan in VirtualBox
The Apple download contains a recovery image called BaseSystem.dmg
which needs to be copied to a correctly partitions and formatted recovery USB or ISO.
- Download the OS X El Capitan installer
- Note for Windows users running Linux from VirtualBox:
- you already downloaded
InstallOSX.dmg
to your USB drive, so skip this step
- you already downloaded
- Visit Apple's official "How to upgrade to El Capitan" documentation
- Click "Download OS X El Capitan" in Step 4
InstallOSX.dmg
will be about 6GB in yourDownloads
folder
- Note for Windows users running Linux from VirtualBox:
- Install HFS+ tools for Linux
- See
install-mac-tools.sh
below - Note for Windows users running Linux from VirtualBox:
- choose to download to your USB drive, NOT
Downloads
- run the script from your USB drive, NOT
Downloads
- choose to download to your USB drive, NOT
- Right-Click on the view
Raw
link, chooseSave as
, and select theDownloads
folder - Open a
Terminal
and runbash install-mac-tools.sh
from theDownloads
folder
pushd ~/Downloads bash install-mac-tools.sh
- See
- Create
el-capitan-recue.iso
- See
linux-create-bootable-macos-recovery-image.sh
below - Note for Windows users running Linux from VirtualBox:
- choose to download to your USB drive, NOT
Downloads
- run the script from your USB drive, NOT
Downloads
- choose to download to your USB drive, NOT
- Right-Click on the view
Raw
link, chooseSave as
, and select theDownloads
folder - Open a
Terminal
and runbash linux-create-bootable-macos-recovery-image.sh
from theDownloads
folder
pushd ~/Downloads bash linux-create-bootable-macos-recovery-image.sh
- See
You can of course run each command of the scripts by hand, but since it's deeply nested (.dmg
containing a .pkg
containing another .dmg
with another .dmg
inside), and requires loopback mounts, it's a rather tedious and mundane process.
You will need a 32GB+ USB drive, ExFAT formatted.
You should copy ElCapitanInstallESD.dmg
from Downloads
to your USB drive.
I had two other dependencies I had to install before the script would run successfully:
empty*img.bz2
from bootableinstallersudo apt-get install mac-fdisk-cross