How to Install macOS High Sierra: A Comprehensive Guide
macOS High Sierra, released in 2017, brought several improvements over its predecessors, including the Apple File System (APFS), enhanced Metal graphics technology, and improvements to Safari. While it’s an older operating system, some users may still need or want to install it, whether for legacy software compatibility, testing purposes, or restoring an older Mac. This comprehensive guide will walk you through the process of installing macOS High Sierra, covering everything from preparation to troubleshooting.
## Before You Begin: Preparation is Key
Before diving into the installation process, meticulous preparation is crucial to ensure a smooth and successful experience. This includes checking compatibility, backing up your data, and obtaining the necessary installation files.
### 1. Check Compatibility
First and foremost, confirm that your Mac is compatible with macOS High Sierra. Apple officially supports the following Mac models:
* iMac (Late 2009 or newer)
* MacBook (Late 2009 or newer)
* MacBook Pro (Mid 2010 or newer)
* MacBook Air (Late 2010 or newer)
* Mac Mini (Mid 2010 or newer)
* Mac Pro (Mid 2010 or newer)
If your Mac isn’t listed, attempting to install High Sierra could lead to compatibility issues or even brick your device. You can quickly check your Mac’s model by clicking the Apple menu in the top-left corner of your screen and selecting “About This Mac.”
### 2. Back Up Your Data
**This is the most critical step.** Installing a new operating system can sometimes lead to data loss. Before proceeding, create a complete backup of your Mac’s hard drive. Here are a few methods:
* **Time Machine:** Apple’s built-in backup utility is the easiest and most recommended option. Connect an external hard drive with sufficient storage space to your Mac. Open System Preferences, click on Time Machine, and select your external drive as the backup disk. Then, click “Back Up Now” to create a full system backup. Ensure the external drive is formatted as Mac OS Extended (Journaled) for optimal performance with Time Machine.
* **Carbon Copy Cloner or SuperDuper!:** These are third-party cloning utilities that create bootable copies of your hard drive. They offer more advanced features than Time Machine, such as incremental backups and scheduling options. They are excellent for creating a complete, bootable replica of your current system. Choose the tool that best fits your needs and budget.
* **Manual Backup:** For specific files or folders, you can manually copy them to an external hard drive or cloud storage service like iCloud Drive, Google Drive, or Dropbox. This is suitable for backing up only essential documents, photos, and other important data.
Regardless of the method you choose, **verify that the backup is complete and accessible** before proceeding with the installation. Trying to restore from a corrupted backup is a frustrating experience.
### 3. Download macOS High Sierra
Since macOS High Sierra is no longer available in the Mac App Store for all users, you may need to find an alternative source. Here are a few options:
* **Previously Downloaded:** If you previously downloaded High Sierra from the Mac App Store, it might still be available in your purchase history. Open the Mac App Store, click on your profile icon in the bottom-left corner, and check your purchased apps list.
* **Apple’s Support Website:** Apple occasionally provides download links for older macOS versions on its support website. Search for “Download macOS High Sierra” on Apple’s website to check if a direct download link is available. Keep in mind this is not always available.
* **Third-Party Websites:** Be extremely cautious when downloading macOS installers from third-party websites. Only download from reputable sources to avoid malware or corrupted files. Always scan downloaded files with antivirus software before opening them.
Once you find a reliable source, download the macOS High Sierra installer. The downloaded file will typically be a .dmg file.
### 4. Create a Bootable USB Drive (Recommended)
Creating a bootable USB drive is the recommended method for installing macOS High Sierra. This allows for a clean installation and is generally more reliable than upgrading from within the existing operating system.
**You will need:**
* A USB drive with at least 16GB of storage space.
* The downloaded macOS High Sierra installer (.dmg file).
* Disk Utility (built into macOS).
* Terminal (also built into macOS).
**Steps:**
1. **Erase the USB Drive:** Connect the USB drive to your Mac. Open Disk Utility (Applications > Utilities > Disk Utility). Select the USB drive in the left sidebar. Click the “Erase” button in the toolbar. In the Erase dialog box, enter a name for the drive (e.g., “HighSierraInstaller”). Choose “Mac OS Extended (Journaled)” as the format. Select “GUID Partition Map” as the scheme. Click “Erase.” **Warning: This will erase all data on the USB drive. Ensure you have backed up any important files.**
2. **Mount the macOS High Sierra Installer:** Double-click the downloaded .dmg file to mount it. A volume named “Install macOS High Sierra” should appear on your desktop or in Finder.
3. **Use the `createinstallmedia` Command:** Open Terminal (Applications > Utilities > Terminal). Type or paste the following command, replacing `YourUSBDriveName` with the actual name of your USB drive (e.g., HighSierraInstaller):
bash
sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia –volume /Volumes/YourUSBDriveName –applicationpath /Applications/Install\ macOS\ High\ Sierra.app –nointeraction
**Explanation of the command:**
* `sudo`: This command requires administrator privileges, so you will be prompted to enter your password.
* `/Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia`: This specifies the path to the `createinstallmedia` tool, which is included within the macOS installer application. The backslashes are used to escape spaces in the path.
* `–volume /Volumes/YourUSBDriveName`: This specifies the volume (USB drive) where the installer will be created. Replace `YourUSBDriveName` with the name you gave your USB drive when you erased it.
* `–applicationpath /Applications/Install\ macOS\ High\ Sierra.app`: This specifies the path to the macOS High Sierra installer application.
* `–nointeraction`: This option prevents the command from prompting for confirmation, making the process automatic.
4. **Enter Your Password:** Press Enter. You will be prompted to enter your administrator password. Type your password and press Enter. Note that you won’t see any characters as you type your password in Terminal.
5. **Wait for the Process to Complete:** The process of creating the bootable USB drive will take some time (usually 20-45 minutes), depending on the speed of your USB drive and Mac. Terminal will display the progress. Do not interrupt the process. It is complete when Terminal displays “Install media now available at /Volumes/Install macOS High Sierra”.
6. **Eject the USB Drive:** Once the process is complete, eject the USB drive from your Mac.
### 5. Gather Apple ID and Password (If Applicable)
If you plan to use iCloud services after installing macOS High Sierra, make sure you have your Apple ID and password readily available.
## Installing macOS High Sierra
Now that you have prepared everything, you can proceed with the installation.
### 1. Boot from the USB Drive
1. **Connect the Bootable USB Drive:** Connect the bootable USB drive to the Mac you want to install macOS High Sierra on.
2. **Restart Your Mac:** Click the Apple menu in the top-left corner of your screen and select “Restart.”
3. **Hold Down the Option Key:** Immediately after your Mac starts to restart (when the screen goes black), press and hold down the **Option (⌥)** key on your keyboard.
4. **Select the USB Drive:** Continue holding down the Option key until you see the Startup Manager screen. This screen displays a list of bootable volumes. Use the arrow keys to select the USB drive you created (it should be named “Install macOS High Sierra” or the name you gave it) and press Enter.
If your Mac starts up normally instead of booting from the USB drive, it means you weren’t holding down the Option key at the correct time. Restart your Mac and try again, making sure to press and hold the Option key immediately after the screen goes black.
### 2. Install macOS High Sierra
1. **Select Language:** After booting from the USB drive, you will be presented with a language selection screen. Choose your preferred language and click the arrow button.
2. **macOS Utilities Window:** You will see the macOS Utilities window. Here, you have several options:
* **Restore From Time Machine Backup:** If you want to restore your Mac from a Time Machine backup, select this option and follow the on-screen instructions. This will erase the existing data on your hard drive and replace it with the data from your backup.
* **Install macOS:** To perform a clean installation of macOS High Sierra, select this option. This will erase the existing data on your hard drive and install a fresh copy of the operating system.
* **Disk Utility:** If you need to erase or format your hard drive before installing macOS, select this option. This is generally necessary if you are having problems with the installation or if you want to ensure a completely clean installation.
3. **Erase Your Hard Drive (If Necessary):** If you are performing a clean installation or if you need to erase your hard drive due to issues, select “Disk Utility” and click “Continue.”
* Select your hard drive in the left sidebar. (usually named Macintosh HD, or similar)
* Click the “Erase” button in the toolbar.
* Enter a name for your hard drive (e.g., “Macintosh HD”).
* Choose **APFS** (Apple File System) as the format. **Important: APFS is highly recommended for SSD drives, which are common in newer Macs. If you are installing on an older Mac with a spinning hard drive (HDD), Mac OS Extended (Journaled) might be more suitable for performance reasons. Research which file system is optimal for your hardware.**
* Select “GUID Partition Map” as the scheme.
* Click “Erase.”
* Once the process is complete, quit Disk Utility to return to the macOS Utilities window.
4. **Select “Install macOS” and Click “Continue.”
**
5. **Agree to the License Agreement:** Read the license agreement and click “Agree” to proceed.
6. **Select the Installation Disk:** Choose the hard drive where you want to install macOS High Sierra (e.g., “Macintosh HD”) and click “Install.”
7. **Wait for the Installation to Complete:** The installation process will take a significant amount of time (usually 30-60 minutes), depending on the speed of your Mac. Your Mac will restart several times during the process. Do not interrupt the installation.
### 3. Setup Assistant
Once the installation is complete, your Mac will restart and the Setup Assistant will guide you through the initial configuration process.
1. **Select Your Country or Region:** Choose your country or region from the list.
2. **Keyboard Layout:** Select your keyboard layout.
3. **Transfer Information to This Mac:** You can choose to transfer information from another Mac, a Time Machine backup, or a Windows PC. If you are performing a clean installation, select “Don’t transfer any information now.”
4. **Enable Location Services:** Choose whether to enable Location Services.
5. **Apple ID:** Enter your Apple ID and password to sign in to iCloud and other Apple services. You can also choose to skip this step and sign in later.
6. **Create a Computer Account:** Enter your name, account name, and password to create a user account on your Mac.
7. **Express Setup:** You can choose to use Express Setup to quickly configure your Mac with default settings. Alternatively, you can customize the settings manually.
8. **Choose Your Time Zone:** Select your time zone.
9. **Analytics:** Choose whether to share analytics data with Apple.
10. **Siri:** Choose whether to enable Siri.
After completing the Setup Assistant, you will be logged into your new macOS High Sierra installation.
## Troubleshooting Common Issues
Even with careful preparation, you might encounter issues during the installation process. Here are some common problems and their solutions:
* **”An error occurred while preparing the installation” or “This copy of the Install macOS High Sierra application is damaged.”** This usually indicates a corrupted installer file. Download the installer again from a reliable source.
* **Mac won’t boot from the USB drive:** Ensure that the USB drive is properly formatted and bootable. Verify that you are holding down the Option key immediately after restarting your Mac. Also, check your Startup Disk settings in System Preferences (if accessible from your current OS) to ensure booting from external media is allowed.
* **Installation gets stuck or freezes:** Try restarting your Mac and booting from the USB drive again. If the problem persists, try erasing your hard drive using Disk Utility and then reinstalling macOS. In rare cases, hardware incompatibility can cause this issue. Run Apple Diagnostics (hold down the D key during startup) to check for hardware problems.
* **”macOS could not be installed on your computer” error:** This can be caused by various issues, such as insufficient disk space, corrupted system files, or hardware problems. Make sure you have enough free space on your hard drive. Try erasing your hard drive and reinstalling macOS. Running Apple Diagnostics can also help identify hardware issues.
* **No Wi-Fi after installation:** Sometimes, older Macs may require manual installation of Wi-Fi drivers after a clean installation. Search online for the specific Wi-Fi driver for your Mac model and macOS High Sierra.
* **Slow performance after installation:** If you installed macOS High Sierra on an older Mac with an HDD (spinning hard drive), consider upgrading to an SSD (solid state drive). This can significantly improve performance. Also, close unnecessary applications and processes to free up system resources.
## Post-Installation Tasks
After successfully installing macOS High Sierra, there are a few things you should do to ensure your system is up-to-date and secure.
* **Update macOS:** Check for software updates by clicking the Apple menu and selecting “Software Update.” Install any available updates to ensure you have the latest security patches and bug fixes.
* **Install Applications:** Install your favorite applications from the Mac App Store or other trusted sources.
* **Configure iCloud:** Sign in to iCloud to sync your contacts, calendars, photos, and other data across your devices.
* **Set Up Time Machine:** Configure Time Machine to automatically back up your data to an external hard drive.
* **Enable FileVault:** Enable FileVault disk encryption to protect your data from unauthorized access.
* **Verify Compatibility of Older Software:** If you are using High Sierra for legacy software compatibility, test the software thoroughly after installation to ensure it functions as expected.
## Conclusion
Installing macOS High Sierra can breathe new life into an older Mac or provide a platform for running legacy software. By following this comprehensive guide, you can successfully install High Sierra and enjoy its features. Remember to back up your data before you start. With careful preparation and attention to detail, you can have a smooth and trouble-free installation experience. Always prioritize data safety and download installers from reputable sources to protect your system from malware. Good luck!