Fixing 0x00000001 APC_INDEX_MISMATCH Stop Code on Windows 10 & 11 – Step by Step

Short Answer

The **APC_INDEX_MISMATCH** (0x00000001) Blue Screen of Death (BSOD) occurs when the kernel detects an inconsistency in memory addresses, often related to hardware or driver issues. While it can be frustrating, this error is usually fixable with basic troubleshooting steps.

Overview

The **APC_INDEX_MISMATCH** stop code is a critical system error that forces Windows 10 and 11 into a BSOD. It typically appears during startup, shutdown, or when accessing certain applications, indicating a problem with how the operating system manages memory or processes.

This error can be caused by corrupted system files, faulty hardware (like RAM), incompatible drivers, or issues with Windows kernel-mode components. Unlike some other BSODs, **APC_INDEX_MISMATCH** is not always linked to a single driver but may involve multiple system processes.

Common Causes

– Corrupted system files due to improper shutdowns or disk errors.
– Faulty RAM modules causing memory address mismatches.
– Outdated or incompatible drivers, especially those related to hardware acceleration (GPU, storage controllers).
– Conflicts between third-party applications and Windows kernel components.
– Malware or system corruption affecting critical processes.

Step-by-Step Fixes

1. Run System File Checker (SFC) and DISM

Corrupted system files are a frequent cause of this BSOD. Use the following commands to repair them:

sfc /scannow

This will scan your system for corruption and attempt repairs automatically.

DISM /Online /Cleanup-Image /RestoreHealth

Wait for both processes to complete before restarting your PC.

2. Check for Disk Errors

A failing hard drive or RAM can trigger this error. Run **chkdsk** from Command Prompt (Admin) to check for disk issues:

chkdsk /f /r

This will scan your drive and attempt repairs, including bad sectors.

For RAM-related problems, use **Windows Memory Diagnostic**:
1. Press **Win + R**, type `mdsched.exe`, and hit Enter.
2. Select the option to run a standard test or extended test (recommended).
3. Restart your PC and check for errors during the scan.

3. Update or Reinstall Drivers

Outdated drivers, especially GPU-related ones, can cause this BSOD. To update them:
1. Open **Device Manager** by pressing **Win + X** and selecting it.
2. Look under sections like **Display adapters**, **Storage controllers**, or **System devices**.
3. Right-click any device with a yellow exclamation mark (if present) and select **Update driver**.
4. Choose **”Search automatically for drivers”** and follow the prompts.

1. In Device Manager, right-click the driver (e.g., GPU or storage controller).
2. Select **Uninstall device**, then check **”Delete the driver software for this device”**.
3. Restart your PC to force Windows to reinstall the driver.

4. Test Hardware Components

Faulty hardware can lead to memory inconsistencies:
– **RAM**: Reseat modules or test them one at a time.
– **GPU**: If using discrete graphics, try removing it (if possible) or updating drivers.
– **Storage devices**: Check for failing sectors or replace faulty SSDs/HDDs.

5. Disable Fast Startup

Fast Startup can sometimes cause conflicts with kernel processes:
1. Open **Control Panel** and go to **Power Options**.
2. Click **”Choose what the power buttons do”**.
3. Under **”Shutdown settings”**, uncheck **”Turn on fast startup (recommended)”**.
4. Save changes and restart your PC.

6. Check for Malware

Malware can corrupt system files or interfere with kernel operations:
– Run a full scan using **Windows Defender** or trusted third-party antivirus software.
– Ensure your malware protection is up to date before scanning.

7. Review Recent System Changes
If the BSOD started after installing new hardware, software, or drivers:
– Roll back driver updates if possible.
– Uninstall recently added applications via **Settings > Apps**.
– Revert any BIOS/UEFI changes that may have caused instability.

FAQ

What does APC_INDEX_MISMATCH mean?

**APC_INDEX_MISMATCH** indicates the kernel detected an invalid memory address while processing an **Asynchronous Procedure Call (APC)**. This usually happens when a driver or hardware component tries to access memory incorrectly.

Is this error common in Windows 10 and 11?

Can I fix it without reinstalling Windows?

In most cases, yes. Running **SFC**, updating drivers, checking RAM, and disabling Fast Startup usually resolve the issue. Only reinstall as a last resort if corruption is severe.

Does this error always require hardware replacement?

No. While faulty RAM or storage can cause it, many instances are resolved by software fixes like driver updates or system file repairs.

What should I do if the BSOD keeps recurring after fixes?

If the problem persists, check for hardware failures (especially RAM) or consider a clean Windows installation. Contact Microsoft Support if needed.

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Last Updated: December 07, 2025
Tested on: Windows 10 (22H2) & Windows 11 (23H2)