macOS User Guide
- Welcome
-
- Change System Preferences
- Change your desktop picture
- Add your email and other accounts
- Use a screen saver
- Change the picture for you or others in apps
- Set up other users on your Mac
- Set up Screen Time for yourself
- Change the system language
- Make it easier to see what’s on the screen
- Use accessibility features
- Run Windows on your Mac
-
- Use Continuity across your devices
- Stream audio and video with AirPlay
- Use your iPad as a second display
- Hand off between devices
- Insert photos and documents from iPhone or iPad
- Insert sketches from iPhone or iPad
- Copy and paste between devices
- Use Apple Watch to unlock your Mac
- Make and receive phone calls on your Mac
- Control accessories in your home
- Send files between devices with AirDrop
- Use AirPods with your Mac
-
- Manage cookies and other website data in Safari
- Use Private Browsing in Safari
- View privacy reports in Safari
- Understand passwords
- Reset your Mac login password
- Use keychains to store passwords
- Set up your Mac to be secure
- Guard your privacy
- Use Sign in with Apple for apps and websites
- Protect your Mac from malware
- Control access to your camera
- Find a missing device
- Resources for your Mac
- Resources for your Apple devices
- Copyright
Check your device’s Thunderbolt connection to Mac
If a Thunderbolt device isn’t working properly, it might not be correctly connected to your computer.
Check your Mac: Connect another device to the Thunderbolt port on your Mac. If you can’t use that device, restart your Mac. If you still can’t use a device with the port, your Mac may need to be serviced. See Find how to service or repair your Mac.
Check chained devices: Disconnect all devices and cables from your Mac, then connect the device directly to your computer using its cable. If the device functions correctly, there may be a problem with one of the other devices. Try reconnecting the other devices and cables to your Mac, one by one. When you find the device causing the problem, review its documentation for further troubleshooting steps.