Erasing and reinstalling macOS is a reliable way to resolve deep system corruption, prepare a Mac for sale, or start fresh with a clean install. This guide walks you through the two paths Apple supports today — Erase All Content and Settings for most users, and Recovery Mode for deeper repairs.
Start Here: Choose the Right Path
Before you follow a multi-step Recovery Mode procedure, confirm which tool you actually need.
- Erase All Content and Settings (preferred) — Fastest, safest factory reset. Keeps the installed macOS in place but wipes all user data, accounts, settings, apps, Touch ID data, Apple ID sign-ins, and Find My activation. Available on Apple Silicon and T2 Intel Macs running macOS Monterey or later. Use this for selling, recycling, handing off to another user, or simply starting fresh.
- Recovery Mode reinstall — Required when the Mac will not boot, the existing install is damaged, the internal drive was replaced, or you are moving between macOS versions (for example downgrading or installing a version that did not ship with the Mac).
For most users preparing a Mac for sale or a fresh start, Erase All Content and Settings is the right choice.
Option 1: Erase All Content and Settings
- Back up anything you want to keep to Time Machine or iCloud
- Open System Settings (or System Preferences on older macOS)
- Go to General > Transfer or Reset
- Click Erase All Content and Settings
- Authenticate with your administrator password
- Follow the prompts to sign out of your Apple ID and confirm
The Mac reboots into a clean Setup Assistant in a few minutes. This method automatically handles Activation Lock, unenrolls from MDM (if the MDM allows), and removes Bluetooth pairings — making it the preferred factory reset for almost every situation.
Option 2: Full Reinstall via Recovery Mode
Use this path when the Mac cannot boot, the install is corrupt, or you need a different macOS version.
Before You Begin
- Back up your data — erasing is irreversible
- Sign out of iCloud (System Settings > Apple ID > Sign Out) to release Activation Lock
- Unenroll from MDM if the device is managed
- Plug in the power adapter on laptops
- Connect to a reliable Wi-Fi network — Recovery needs it for activation and downloads
Step 1: Enter Recovery Mode
The entry method depends on your Mac's processor.
| Mac Generation | Key Combination | What It Does |
|---|---|---|
| Apple Silicon (M1+) | Hold power button until "Loading startup options" appears, click Options | Loads local Recovery partition |
| Intel with T2 | Command + R | Reinstalls current macOS |
| Intel with T2 | Option + Command + R | Installs latest compatible macOS |
| Intel with T2 | Shift + Option + Command + R | Installs macOS that originally shipped with the Mac |
| Intel without T2 | Command + R | Local Recovery if available |
| Intel (any) | Option + Command + R | Internet Recovery (downloads from Apple) |
On Apple Silicon, always shut down first, then press and hold the power button until the startup options screen appears. On Intel, power on the Mac and hold the key combination immediately until you see the Apple logo or a spinning globe (globe indicates Internet Recovery).
Step 2: Authenticate
When prompted, select an administrator account and enter the password. If the Mac uses FileVault, you will need to unlock the disk before continuing.
Step 3: Erase the Drive in Disk Utility
- In the Recovery Assistant window, select Disk Utility and click Continue
- In the sidebar, click View > Show All Devices
- Select the top-level internal drive (not just the
Macintosh HDvolume) - Click Erase
- Set these options:
- Name:
Macintosh HD - Format: APFS
- Scheme: GUID Partition Map
- Name:
- Click Erase and wait for the operation to complete
- Quit Disk Utility to return to the Recovery Assistant
If you see a Macintosh HD - Data volume alongside Macintosh HD, erasing the top-level device removes both.
Step 4: Reinstall macOS
- Select Reinstall macOS and click Continue
- Agree to the license terms
- Choose the freshly erased
Macintosh HDvolume as the destination - Click Install and wait — the Mac will reboot one or more times
Keep the Mac plugged in and do not close the lid. Installation typically takes 30 to 60 minutes locally, or one to three hours via Internet Recovery.
Step 5: Activation and Setup
After installation, the Mac boots into Setup Assistant. If Activation Lock is enabled, you must sign in with the Apple ID previously associated with the Mac. If you are preparing the Mac for a new owner, shut down now at the Setup Assistant screen — do not complete setup yourself.
Troubleshooting
"An error occurred preparing the software update"
The installer cannot reach Apple's servers or the system clock is wrong. Open Terminal from the Utilities menu in Recovery, run date to check the clock, and if needed run ntpdate -u time.apple.com. Verify Wi-Fi connectivity, then retry.
Apple ID will not activate the Mac
Confirm the Apple ID matches the one previously signed in. Check the account status at the Apple ID website. If Find My was enabled by a previous owner, only that person can unlock it — Apple cannot bypass Activation Lock without proof of purchase.
Recovery Assistant loop or blank screen
Shut down fully (hold power for 10 seconds), then retry. On Apple Silicon, release the power button as soon as "Loading startup options" appears. On Intel, try a different key combination — if Command + R fails, use Option + Command + R to force Internet Recovery.
Internet Recovery is slow or failing
Internet Recovery downloads a multi-gigabyte installer over Wi-Fi. Move closer to the router, use a 5 GHz network, or connect via USB Ethernet adapter. Apple's servers occasionally throttle during major macOS releases — retry during off-peak hours.
Disk Utility does not show the internal drive
Enable View > Show All Devices. If the drive still does not appear, the storage may have failed. Run Apple Diagnostics by holding D at boot on Intel Macs, or from the Options screen on Apple Silicon.