Fix Windows 11 / Windows 10 Boot Errors (Complete Repair Guide)

Windows boot errors can prevent your PC from starting properly. These errors may appear after updates, power failure, disk corruption, or improper shutdown. This guide explains all common Windows 10 and Windows 11 boot problems and how to fix them step by step.

Common Windows Boot Errors

• Windows failed to start
• Automatic Repair couldn’t repair your PC
• Boot Device Not Found
• INACCESSIBLE_BOOT_DEVICE
• Missing or corrupt BCD
• Black screen with cursor
• Windows stuck on loading screen

Step 1: Enter Windows Recovery Environment (WinRE)

You must first enter the recovery environment.

Method 1: Automatic

Restart the PC 2–3 times while Windows is loading. Windows will automatically enter recovery mode.

Method 2: Using Bootable USB

1. Insert Windows 10/11 bootable USB
2. Boot from USB
3. Click Repair your computer
4. Select Troubleshoot

Step 2: Use Startup Repair (First Try)

Startup Repair automatically fixes common boot problems.

1. Troubleshoot
2. Advanced options
3. Startup Repair
4. Select Windows installation

Wait for the process to complete and restart.

Step 3: Boot into Safe Mode

Safe Mode helps diagnose driver or software issues.

1. Advanced options
2. Startup Settings
3. Restart
4. Press 4 or F4 for Safe Mode

If Windows starts in Safe Mode, uninstall recent updates or drivers.

Step 4: Fix Boot Using Command Prompt

If Startup Repair fails, use manual repair commands.

Open Command Prompt

1. Advanced options
2. Command Prompt

Check Disk Errors

chkdsk C: /f /r

Replace C: if Windows is installed on another drive.

Step 5: Repair Boot Records (MBR / BCD)

Run the following commands one by one:

bootrec /fixmbr
bootrec /fixboot
bootrec /scanos
bootrec /rebuildbcd

If asked to add installation to boot list, press Y.

Step 6: Fix EFI Boot (UEFI Systems)

For UEFI systems, rebuild EFI boot files.

diskpart
list disk
select disk 0
list vol
select vol X
assign letter=S:
exit

Then run:

bcdboot C:\Windows /s S: /f UEFI

Step 7: Fix INACCESSIBLE_BOOT_DEVICE Error

This error usually occurs due to storage mode issues.

• Enter BIOS
• Change SATA mode (AHCI / RAID)
• Match previous configuration

Restart and test again.

Step 8: System Restore

If Windows worked previously, restore to an earlier point.

1. Advanced options
2. System Restore
3. Select restore point

System Restore does not remove personal files.

Step 9: Uninstall Windows Updates

Faulty updates may cause boot failure.

1. Advanced options
2. Uninstall Updates
3. Uninstall latest quality update

Step 10: Reset Windows (Last Option)

If nothing works, reset Windows.

1. Troubleshoot
2. Reset this PC
3. Keep my files

Apps will be removed, but files remain safe.

Advanced Tips

• Disconnect external devices
• Check HDD/SSD health
• Update BIOS if needed
• Backup data before major repair

When to Reinstall Windows

Reinstall Windows if:

• System files are severely damaged
• Boot repair fails repeatedly
• Disk structure is corrupted

Reinstallation ensures long-term stability.

Conclusion

Most Windows 10 and Windows 11 boot errors can be fixed without reinstalling the operating system. By following this complete guide step by step, you can safely diagnose and repair boot issues.

Always start with simple solutions and proceed to advanced fixes only when needed.