How to Create a Bootable macOS El Capitan ISO

Are you looking for a way to create a bootable macOS El Capitan ISO? This article will guide you through the process of creating an ISO file from a DMG file and installing it on your computer.

First, let's start with the basics. A DMG file is a disk image file that contains an installer package for macOS. To create an ISO file, we'll need to use a tool called `hdiutil`. This command-line utility allows us to convert DMG files to ISO format.

Step 1: Download the Installer Package

The first step in creating an ISO file is to download the installer package from Apple's website. You can find the link to the installer package on the Apple Support page for macOS El Capitan.

Once you have downloaded the installer package, extract it using a tool like `pkgutil`. This will create a folder containing the installer files.

Step 2: Create an ISO File

To create an ISO file from the DMG file, we'll use the `hdiutil` command. Here's how to do it:

1. Open Terminal and navigate to the folder where you extracted the installer package.

2. Use the following command to convert the DMG file to ISO format:

```

hdiutil convert /path/to/dmg -format UDTO -o ~/Desktop/ElCapitan.iso

```

Replace `/path/to/dmg` with the path to your DMG file.

Step 3: Create a Bootable USB Drive

Once you have created the ISO file, we'll need to create a bootable USB drive using the `hdiutil` command. Here's how to do it:

1. Plug in your USB flash drive.

2. Use the following command to erase the USB drive:

```

sudo diskutil erase /dev/disk2s1

```

Replace `/dev/disk2s1` with the name of your USB flash drive.

3. Use the following command to create a bootable installer on the USB drive:

```

sudo hdiutil attach /path/to/ElCapitan.iso -noverify -mountpoint /Volumes/

```

Replace `/path/to/ElCapitan.iso` with the path to your ISO file.

4. Once you have created the bootable installer, you can use it to install macOS El Capitan on your computer.

Step 4: Install macOS El Capitan

To install macOS El Capitan from the bootable USB drive, follow these steps:

1. Plug in the USB flash drive and restart your computer.

2. Press the 'C' key repeatedly while booting up your computer to select the USB drive as the startup disk.

3. Follow the installation prompts to complete the installation process.

That's it! You should now have a bootable macOS El Capitan ISO file that you can use to install or upgrade your operating system.

Creating a bootable macOS El Capitan ISO file is a straightforward process that requires just a few commands and some basic knowledge of terminal commands. By following the steps outlined in this article, you should be able to create an ISO file from a DMG file and install it on your computer.

Mac os el capitan iso