Error: Unable to Start Windows Due to Missing or Corrupt File \Windows\System32\config\system

If you encounter an error message stating "Unable to start Windows due to a missing or corrupt file \Windows\System32\config\system" during boot, it indicates an issue with the system registry. This problem can arise from various causes such as sudden power loss, hard drive failure, or malware infection.

What Is This Error and Why Does It Happen?

The SYSTEM file is part of the config folder and a crucial component of the Windows system registry. It contains vital OS settings, and any corruption of this file prevents Windows from starting properly. Possible causes include:

  • Improper shutdowns (e.g., abrupt power loss).
  • Hard drive failure or corruption.
  • Malware or virus infection.
  • Failed or incorrect Windows updates or driver installations.

How to Fix the Problem

Method 1: Use System Restore

  1. Insert a Windows installation disc or bootable USB drive and restart your computer.
  2. Select your language and click Next.
  3. Click on Repair your computer.
  4. Select System Restore and follow the on-screen instructions to roll back your system to a previous state.

Method 2: Restore the File Using Command Prompt

If no restore point is available, you can attempt to fix the registry file via Command Prompt:

  1. Open Command Prompt from the bootable media.
  2. Navigate to the config directory: 
    cd C:\Windows\System32\config
  3. Backup the corrupted file: 
    ren SYSTEM SYSTEM.bak
  4. Copy the backup file from the RegBack folder: 
    copy C:\Windows\System32\config\RegBack\SYSTEM C:\Windows\System32\config\
  5. Restart your computer.

Method 3: Run CHKDSK and SFC Commands

Sometimes, the issue is caused by a damaged file system. Use CHKDSK and SFC to scan and fix system files:

  1. Open Command Prompt from the installation media.
  2. Run the disk check command: 
    chkdsk C: /f /r
  3. Then run the system file check command: 
    sfc /scannow

Method 4: Reinstall Windows

If none of the above methods work, you may need to reinstall Windows. Make sure to back up all your important data before proceeding with a fresh installation.