5 Ways to Fix S.M.A.R.T. Errors During macOS Installation

Common symptoms

• macOS installation fails with S.M.A.R.T. error
• Warning about hard drive failure during setup
• Installation stops with disk verification error
• System reports imminent drive failure

Possible causes

• Hard drive developing bad sectors
• Drive experiencing read/write errors
• Aging hard drive nearing end of life
• Physical damage to drive platters or heads

Step-by-step solution

1. Backup Critical Data Immediately

   Secure important files before drive fails completely

   Boot from external drive or Recovery Mode
   Use Target Disk Mode to access files from another Mac
   Copy essential documents, photos, and files to external storage
   Prioritize irreplaceable personal data

   Warning: S.M.A.R.T. errors indicate imminent drive failure - backup immediately

2. Run First Aid on the Drive

   Attempt to repair minor disk errors

   Boot into Recovery Mode (Command + R)
   Open Disk Utility
   Select the failing drive
   Click First Aid and run repair
   If successful, attempt macOS installation again

   Note: This may temporarily resolve minor issues but won't fix hardware problems

3. Create Bootable macOS Installer

   Prepare external installation media

   Download macOS installer from App Store
   Format USB drive (16GB+) as Mac OS Extended (Journaled)
   Use createinstallmedia command or third-party tool
   Boot from USB installer instead of internet recovery

   Note: External installer may bypass some drive verification steps

4. Format Drive and Reinstall

   Completely erase drive and attempt fresh installation

   Boot from external installer
   Open Disk Utility
   Select drive and click Erase
   Choose GUID Partition Map scheme
   Format as APFS or Mac OS Extended (Journaled)
   Attempt macOS installation on clean drive

   Warning: This will permanently delete all data on the drive

5. Replace the Hard Drive

   Install new drive as permanent solution

   Purchase compatible replacement drive (SSD recommended)
   Backup data to external drive
   Replace internal drive (may require professional service)
   Install macOS on new drive
   Restore data from backup

   Note: This is the only permanent solution for failing drives

Alternative solutions

• Use external SSD as primary drive temporarily
• Install macOS on external drive as emergency solution
• Try different macOS version that may be less strict about drive health

When to seek professional help

• Drive replacement requires opening laptop/iMac
• Data recovery needed from failing drive
• Multiple S.M.A.R.T. errors indicate complex hardware failure
• Professional data recovery services needed