💡 If you are trying to revive an old Mac, ensure your date and time settings are correct in Recovery Mode, or the installer might fail due to expired security certificates. If you'd like to move forward, let me know: Are you trying to create a bootable USB ?
diskutil unmountDisk /dev/diskN
: If you are already on a Mac, you can use the softwareupdate tool to download the full installer without using the App Store. Open Terminal and type: softwareupdate --fetch-full-installer --full-installer-version 10.15.7 . Download Macos Catalina 10.15.7 Dmg File
Incomplete or corrupted DMG file. You likely downloaded via an unreliable mirror. 💡 If you are trying to revive an
Apple’s macOS is proprietary software. Downloading from Apple is free and legal for use on Apple-branded hardware. Download Macos Catalina 10.15.7 Dmg File