Welcome
- MacBook Air
- MacBook Pro
- iMac
- Mac mini
- Mac Studio
- Mac Pro
What’s new in macOS Sequoia
- Work on the desktop
- What’s in the menu bar?
- Quickly change settings
- What’s in the Apple menu?
- Search with Spotlight
- Use Siri
- Get notifications
- Open apps from the Dock
- Organize your files in the Finder
- Connect to the internet
- Sign in to your Apple Account
- Set up iCloud
- Browse the web
- Preview a file
- Take a screenshot
- Change your display’s brightness
- Adjust the volume
- Use trackpad and mouse gestures
- Use Touch ID
- Print documents
- Keyboard shortcuts
- Apps on your Mac
- Open apps
- Work with app windows
- Tile app windows
- Use apps in full screen
- Use apps in Split View
- Use Stage Manager
- Get apps from the App Store
- Install and reinstall apps from the App Store
- Install and uninstall other apps
- Create and work with documents
- Open documents
- Mark up files
- Combine files into a PDF
- Organize files on your desktop
- Organize files with folders
- Tag files and folders
- Back up files
- Restore files
- Change System Settings
- Choose your desktop picture
- Add and customize widgets
- Use a screen saver
- Add a user or group
- Add your email and other accounts
- Automate tasks with Shortcuts
- Create Memoji
- Change your login picture
- Change the system language
- Increase the size of what’s on your screen
- How to use Siri
- Customize Siri
- Use Siri Suggestions
- Use Siri results
- Add Siri Shortcuts
- Intro to Apple Intelligence
- Find the right words with Writing Tools
- Create original images with Image Playground
- Create your own emoji with Genmoji
- Use Apple Intelligence with Siri
- Summarize notifications and reduce interruptions
- Use ChatGPT with Apple Intelligence
- Apple Intelligence and privacy
- Block access to Apple Intelligence features
- Set up a Focus to stay on task
- Block pop-ups in Safari
- Use Dictation
- Perform quick actions with hot corners
- Send emails
- Send text messages
- Make a FaceTime call
- Edit photos and videos
- Use Live Text to interact with text in a photo
- Start a Quick Note
- Get directions
- Intro to Continuity
- Use AirDrop to send items to nearby devices
- Hand off tasks between devices
- Control your iPhone from your Mac
- Copy and paste between devices
- Stream video and audio with AirPlay
- Make and receive calls and text messages on your Mac
- Use your iPhone internet connection with your Mac
- Share your Wi-Fi password with another device
- Use iPhone as a webcam
- Insert sketches, photos, and scans from iPhone or iPad
- Unlock your Mac with Apple Watch
- Use your iPad as a second display
- Use one keyboard and mouse to control Mac and iPad
- Sync music, books, and more between devices
- Manage Apple Account settings
- Set your Apple Account picture
- What is iCloud?
- What is iCloud+?
- Store files in iCloud Drive
- Share and collaborate on files and folders
- Manage iCloud storage
- Use iCloud Photos
- Get started with Screen Time
- Set up Screen Time for yourself
- Set up Screen Time for a child
- Track app and device usage
- Set time limits for apps and websites
- Set up content and privacy restrictions
- Set up Family Sharing
- Get Family Sharing recommendations
- Add family members to a Family Sharing group
- Remove family members from a Family Sharing group
- Manage sharing and parental settings
- Share a Photo Library
- Collaborate on projects
- Find content shared with you
- Find your family and friends
- Play music
- Watch and listen together with SharePlay
- Listen to podcasts
- Watch TV shows and movies
- Read and listen to books
- Read the news
- Track stocks and the market
- Play games with your friends
- Connect an external display
- Use the camera
- Connect a wireless accessory
- Connect a printer to your Mac
- Connect AirPods to your Mac
- Optimize your Mac battery life
- Optimize storage space
- Burn CDs and DVDs
- Control accessories in your home
- Run Windows on your Mac
- Get started
- Vision
- Hearing
- Mobility
- Speech
- Control what you share
- Set up your Mac to be secure
- Allow apps to see the location of your Mac
- Use Private Browsing
- Keep your data safe
- Understand passwords
- Change weak or compromised passwords
- Keep your Apple Account secure
- Use Mail Privacy Protection
- Use Sign in with Apple for apps and websites
- Find a missing device
- Shut down or restart your Mac
- Start up your Mac in safe mode
- Keep your Mac up to date
- Reinstall macOS
- Erase your Mac
Resources for your Mac
Resources for your Apple devices
Copyright

If you can’t install macOS on an external disk

You can install macOS only on disks with the GUID Partition Table scheme. Use Disk Utility to check your external disk’s partition scheme to make sure it’s the required scheme.

Open Disk Utility for me

Go to the Disk Utility app on your Mac.
Choose View > Show All Devices (a checkmark indicates it’s selected).
Select the external disk in the list on the left.
Disks appear flush left in the list (volumes are indented below disks).
On the right, check whether the description below the disk name mentions GUID Partition Map.
If it doesn’t, you need to reformat the external disk before you can install macOS on it. For information about reformatting an external disk using Disk Utility on Mac, see Erase and reformat a storage device.

Helpful?

Mac User Guide

If you can’t install macOS on an external disk