Recover all your files from a Time Machine backup
If you use Time Machine to back up your Mac, you can recover your files if your system or startup disk is damaged.
Important: You must first reinstall macOS on your Mac before you can restore your files using your Time Machine backup.
If you’re restoring your system because of a problem with your startup disk, repair or replace the disk before following these instructions.
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Before you begin, make sure your Time Machine backup disk is connected and turned on. If your disk is on a network, make sure your Mac is on the same network.
Start up your computer in macOS Recovery:
On a Mac with Apple silicon: Choose Apple menu
On an Intel-based Mac: Choose Apple menu
To reinstall the version of macOS stored on your computer’s built-in recovery disk, including any installed updates, select Reinstall macOS Sonoma in the Recovery window, then click Continue.
See Reinstall macOS.
After macOS finishes installing new system files, Migration Assistant asks if you want to transfer information from another Mac or a Time Machine backup. Select Transfer from a Time Machine Backup, then click Continue.
If necessary, enter the name and password you use to connect to your backup disk. You may also have to enter the password you used to encrypt the backup.
Select the date and time of the backup you want to restore, then follow the onscreen instructions.
After you restore your system, Time Machine may perform a full backup at the next scheduled backup time. This is normal. Time Machine resumes incremental backups after the full backup is completed.