Reinstalling macOS on a disk that has been completely erased using Internet Recovery is a useful troubleshooting step if your Mac's operating system is corrupted or you want to perform a clean installation. Internet Recovery allows you to download macOS directly from Apple's servers. Here's a step-by-step guide on how to do it:
**Important Note:** This process will erase all data on the selected disk, so ensure you have backed up any important files before proceeding.
1. **Power Off Your Mac**: Shut down your Mac completely.
2. **Access Internet Recovery Mode**: To do this, press and hold the following keys simultaneously as you turn on your Mac or restart it: `Option + Command + R`. Keep holding these keys until you see the Apple logo or a spinning globe on the screen. This signifies that your Mac is booting into Internet Recovery Mode.
3. **Connect to a Wi-Fi Network**: Your Mac will need an internet connection to download the macOS installer. Select a Wi-Fi network from the list and enter the necessary credentials if required.
4. **Start Disk Utility**: Once your Mac connects to the internet, you'll be presented with the macOS Utilities window. Select "Disk Utility" and click "Continue."
5. **Erase the Target Disk**: In Disk Utility, locate the internal disk where you want to install macOS. It should appear on the left sidebar. Select it and click the "Erase" button in the toolbar.
- Choose a name for the disk (e.g., "Macintosh HD").
- Select a format (usually "APFS" for modern Macs).
- Click "Erase" to format the disk. This will erase all data on the selected disk.
6. **Quit Disk Utility**: After the erasure is complete, close Disk Utility to return to the macOS Utilities window.
7. **Install macOS**: In the macOS Utilities window, select "Reinstall macOS" and click "Continue."
8. **Choose the Target Disk**: Select the newly erased disk as the installation destination and click "Install."
9. **Download macOS**: Your Mac will now connect to Apple's servers and download the latest version of macOS. The installation process may take some time depending on your internet connection speed.
10. **Complete Setup**: Once macOS is downloaded and installed, your Mac will automatically reboot. Follow the on-screen instructions to set up your Mac, including creating a user account and configuring settings.
11. **Restore Data (Optional)**: After successfully reinstalling macOS, you can restore your files from your backup if you have one. You can do this using Time Machine or another backup method.
That's it!
