For virtual environments, make sure you allocate at least 2 CPU cores, 4GB of system RAM, and explicitly choose inside your environment wizard configuration before booting your freshly generated ElCapitan.iso image.

– As of 2025, Apple has removed older OS X versions from the Mac App Store. You would need an existing Apple ID that previously “purchased” it (even when free) to redownload it.

# 1. Create a blank disk image wrapper hdiutil create -o /tmp/ElCapitan.cdr -size 8000m -layout SPUD -fs HFS+J # 2. Mount the blank image to your system hdiutil attach /tmp/ElCapitan.cdr.dmg -noverify -mountpoint /Volumes/install_build # 3. Use Apple's built-in tool to populate the image sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app --nointeraction # 4. Unmount the newly created installer volume hdiutil detach /Volumes/Install\ OS\ X\ El\ Capitan # 5. Convert the dmg format into a standard ISO format (.cdr) hdiutil convert /tmp/ElCapitan.cdr.dmg -format UDTO -o /tmp/ElCapitan.iso # 6. Move the final working ISO to your desktop mv /tmp/ElCapitan.iso.cdr ~/Desktop/ElCapitan.iso Use code with caution.

This guide covers the legitimate methods to acquire the El Capitan installer and convert it into a clean, working ISO file. Phase 1: Download the Official El Capitan Installer

: When setting up a new virtual machine, select "Apple Mac OS X" as the operating system type and "OS X El Capitan (64-bit)" as the version. Mount your new ElCapitan.iso file as the virtual optical drive before booting the VM for the first time.

If you lose your mouse pointer, shaking the mouse or trackpad makes it grow large temporarily. Making a 10.11.1 ISO Image Work

If you are creating this on a newer Mac (Sierra or later), SIP might interfere with some deep-system modifications, but it generally allows creating installation media. If commands fail, you may need to restart into Recovery Mode and disable SIP temporarily (csrutil disable), though this is rarely required for just creating an ISO.

Use Apple's native createinstallmedia tool hidden inside the installer app to clone the boot files onto your temporary volume.

Download the installer disk image ( InstallOSX.dmg ). Step 2: Extract the Installer Application Double-click InstallOSX.dmg to mount it. Run the InstallOSX.pkg installer package inside.