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0x00000001BSODCritical

0x00000001 — APC Index Mismatch | Blue Screen Fix Guide

APC_INDEX_MISMATCH

Windows 10Windows 11

What Does 0x00000001 Mean?

An APC (Asynchronous Procedure Call) state index mismatch has occurred. This is usually caused by a driver or file system filter with a mismatched sequence of calls to disable and re-enable APCs.

Real-World Causes

  1. 1Faulty file system filter driver
  2. 2Incompatible antivirus or security software
  3. 3Corrupted system files
  4. 4Driver conflict during I/O operations

Symptoms

  • ⚠Blue screen with stop code APC_INDEX_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. 2Run System File Checker (sfc /scannow)
  3. 3Check Windows Update
  4. 4Run DISM /Online /Cleanup-Image /RestoreHealth

Advanced Fix

For experienced users and IT professionals

  1. 1Analyze minidump with WinDbg
  2. 2Check Event Viewer for correlated errors
  3. 3Use Process Monitor to trace system activity
  4. 4Perform clean boot to isolate the cause

Frequently Asked Questions

What causes APC_INDEX_MISMATCH?
An APC (Asynchronous Procedure Call) state index mismatch has occurred. This is usually caused by a driver or file system filter with a mismatched sequence of calls to disable and re-enable APCs.
Can I fix APC Index 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

0x0000000AIRQL not Less or Equal0x0000001EKmode Exception not Handled

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.