This guide helps you diagnose and fix problems related to Windows boot configuration, including BCD corruption, missing boot files, and startup failures.
If you have not already tried the main startup fixes, see the Windows Won’t Boot guide.
Common Symptoms
- “Boot configuration data is missing or contains errors”
- Windows fails to start after an update
- Automatic Repair loop
- Black screen on startup
- System boots to BIOS repeatedly
Quick Fixes
- Restart the PC and disconnect external drives
- Check BIOS boot order
- Run Startup Repair
For deeper startup troubleshooting, see the Advanced Boot Repair guide.
Advanced Fixes
Rebuild the BCD
bootrec /fixmbr
bootrec /fixboot
bootrec /scanos
bootrec /rebuildbcd
If these commands fail or return errors, the Advanced Boot Repair guide includes additional recovery options.
Run System File Checker
sfc /scannow
Run DISM Repair
dism /online /cleanup-image /restorehealth
If system file repairs do not resolve the issue, you may need to use a restore point. See the System Restore Guide for detailed steps.
When to Consider a Reset
If the system still fails to boot after BCD repair and file integrity checks, a Windows Reset or reinstall may be required.