macOS Sierra / Mojave
How to Factory Reset macOS
Before You Start
Back up your data using Time Machine (recommended)
Ensure stable internet connection
Have your Apple ID and password ready (optional)
Set aside 3-5 hours for the complete process
Step 1: Enter Recovery Mode
Turn off your Mac
Press the power button
Immediately press and hold
Command (⌘) + R
Keep holding until you see the Recovery screen (about 5 minutes)
Connect to Wi-Fi when prompted
Enter your Wi-Fi password
Step 2: Erase Your Drive
Select "Disk Utility"
From the sidebar, select "Macintosh HD" (internal drive)
Click "Erase" at the top
Keep default settings in the format options
Click "Erase"
Wait for the process to complete
Verify the free space is available
Exit Disk Utility
Step 3: Reinstall macOS
Select "Reinstall macOS"
Click "Continue"
Read and agree to Apple's terms
Select "Macintosh HD" as installation destination
Click "Install"
Wait for installation (up to 5 hours)
Step 4: Initial Setup
Select region and language
Connect to Wi-Fi
Migration Assistant options:
Restore from Time Machine backup
Select "Don't transfer now" for fresh install
Step 5: Account Setup (Optional)
Apple ID setup:
Enter your Apple ID and password
Skip if selling/giving away the computer
iCloud options:
Keychain (can be disabled)
iCloud Desktop & Documents
Additional features:
Siri setup
Analytics sharing preferences
Important Notes
⚠️ Warning: This process erases all data. Back up important files before starting.
Default formatting options are recommended
Installation time varies by internet speed
Computer will restart several times
Alternative Installation Method
You can also install using a flash drive (bootable installer)
Useful for offline installation
Requires separate preparation steps
After Reset
Verify successful installation
Configure system preferences
Install necessary applications
Restore data if needed
Troubleshooting
If Recovery Mode fails:
Restart and try again
Ensure Command + R is pressed immediately after startup
If installation is slow:
Check internet connection
Connect to faster network if possible
Note: This guide works for both macOS Sierra and Mojave. Some interface elements may vary slightly between versions.
Last updated