The downloaded file is an application ( .app ), not a raw DMG disk image. To use it for a clean install, you must create a bootable USB drive using the Terminal.
: Developers often use the DMG or ISO format to run legacy software in environments like VirtualBox or VMware. System Requirements Before downloading, ensure your Mac is compatible: OS X El Capitan | Specs, reviews and EoL info - InvGate download os x el capitan dmg
If you still need help locating a legitimate installer, reply with your — I can guide you further. The downloaded file is an application (
sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app System Requirements Before downloading, ensure your Mac is
: Download OS X El Capitan (6.2 GB) via the Apple Support macOS Download Page. Format : The file is typically named InstallMacOSX.dmg .