macOS Sierra / Mojave

How to Factory Reset macOS

Mac : Factory reset / Fresh install ( macOS Sierra , Mojave )

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

1. Turn off your Mac

2. Press the power button

3. Immediately press and hold Command (⌘) + R

4. Keep holding until you see the Recovery screen (about 5 minutes)

5. Connect to Wi-Fi when prompted

6. Enter your Wi-Fi password

Step 2: Erase Your Drive

1. Select "Disk Utility"

2. From the sidebar, select "Macintosh HD" (internal drive)

3. Click "Erase" at the top

4. Keep default settings in the format options

5. Click "Erase"

6. Wait for the process to complete

7. Verify the free space is available

8. Exit Disk Utility

Step 3: Reinstall macOS

1. Select "Reinstall macOS"

2. Click "Continue"

3. Read and agree to Apple's terms

4. Select "Macintosh HD" as installation destination

5. Click "Install"

6. Wait for installation (up to 5 hours)

Step 4: Initial Setup

1. Select region and language

2. Connect to Wi-Fi

3. Migration Assistant options:

   • Restore from Time Machine backup

   • Select "Don't transfer now" for fresh install

Step 5: Account Setup (Optional)

1. Apple ID setup:

   • Enter your Apple ID and password

   • Skip if selling/giving away the computer

2. iCloud options:

   • Keychain (can be disabled)

   • iCloud Desktop & Documents

3. 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

1. Verify successful installation

2. Configure system preferences

3. Install necessary applications

4. 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

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Note: This guide works for both macOS Sierra and Mojave. Some interface elements may vary slightly between versions.