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0x00000100BSODCritical

0x00000100 — Loader Block Mismatch | Blue Screen Fix Guide

LOADER_BLOCK_MISMATCH

Windows XPWindows VistaWindows 7Windows 8Windows 10Windows 11

What Does 0x00000100 Mean?

The loader block structure does not match what the kernel expects, indicating a version mismatch between the boot loader and kernel.

Real-World Causes

  1. 1Mismatched bootloader and kernel versions
  2. 2Corrupted boot files
  3. 3Incomplete Windows update

Symptoms

  • ⚠Blue screen with stop code LOADER_BLOCK_MISMATCH
  • ⚠System reboots unexpectedly
  • ⚠Possible data loss from unsaved work

DIY Fix

Beginner-friendly steps you can try at home

  1. 1Restart your computer
  2. 2Use Windows Recovery Environment
  3. 3Run Startup Repair
  4. 4Rebuild BCD with bootrec commands

Advanced Fix

For experienced users and IT professionals

  1. 1Rebuild BCD store manually
  2. 2Use bcdedit to verify boot configuration
  3. 3Repair Master Boot Record with bootrec /fixmbr
  4. 4Reinstall Windows if boot files are corrupted

Frequently Asked Questions

What causes LOADER_BLOCK_MISMATCH?
The loader block structure does not match what the kernel expects, indicating a version mismatch between the boot loader and kernel.
Can I fix Loader Block Mismatch myself?
In many cases yes. Start with basic troubleshooting like restarting, updating drivers, and running System File Checker. If the issue persists, advanced analysis of crash dumps may be needed.

Related Error Codes

0x00000079Mismatched HAL0x0000007BInaccessible Boot Device

About the Author

Windows Troubleshooting Team

Verified against official Microsoft documentation and real-world diagnostic data. Error behavior confirmed across Windows 10, Windows 11, and Windows Server.