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0x00000029SECURITY_SYSTEMStop codeWidely reported

SECURITY_SYSTEM (0x00000029): what it means and how to fix it

Updated Oct 14, 2026 · Checked against Microsoft documentation · How this page is made

Quick answer

The SECURITY_SYSTEM error is a rare blue screen stop code indicating that the Windows security subsystem has encountered an unexpected condition. This error is infrequent and usually points to a conflict within the core security processes of the operating system. Start by running the built-in Windows system file checker to identify and repair corrupted system files.

What it means

What is the SECURITY_SYSTEM error? The SECURITY_SYSTEM error, identified by the code 0x00000029, is a critical stop code that occurs when the Windows security subsystem fails to perform an expected operation. Windows relies on a specific set of background processes to manage user authentication, security tokens, and permission checks. When these processes encounter a state they cannot handle, the operating system halts to prevent potential security vulnerabilities or data corruption. Because this error is rare, it does not typically stem from a single, well-known software bug. Instead, it often indicates that a core system file has become damaged, or that a conflict exists between the security subsystem and a low-level driver. When this happens, Windows stops immediately to protect the integrity of your user account information and system permissions.

Common causes

  • Corrupted system files essential for security operations.
  • Conflicts between security software and Windows core processes.
  • Outdated or incompatible low-level device drivers.
  • Interrupted Windows update processes affecting security components.

How to fix it

Safest and most likely fixes first. Readers' answers to "Did this fix it?" reorder this list over time.

  1. Run the System File Checker

    Use this tool to automatically detect and repair corrupted Windows system files.

    1. Open the Start menu and type cmd.
    2. Right-click Command Prompt and select Run as administrator.
    3. Type sfc /scannow and press Enter.
    4. Wait for the process to reach 100 percent and restart your computer if repairs are performed.
    Did this fix it?

  2. Check for Windows Updates

    Use this to ensure your system has the latest security patches and stability improvements.

    1. Open the Settings app.
    2. Select Windows Update from the left sidebar.
    3. Click Check for updates.
    4. Install any pending updates and restart your computer.
    Did this fix it?

  3. Update your device drivers

    Use this if you have recently installed new hardware or updated your system.

    1. Right-click the Start button and select Device Manager.
    2. Look for any devices marked with a yellow warning icon.
    3. Right-click the device and select Update driver.
    4. Choose Search automatically for drivers.
    Did this fix it?

Is it just you?

25+ Microsoft Q&A threads discuss this. Most recent activity:

Checked Oct 10, 2026. Refreshed automatically every few days.

Sources

Frequently asked questions

Is the SECURITY_SYSTEM error a sign of a virus?

While it is possible for malicious software to interfere with security processes, this error is more commonly caused by damaged system files or driver conflicts rather than a direct infection.

Does this error mean I need to reinstall Windows?

Not necessarily. Most instances of this error can be resolved by running system repair tools or ensuring your operating system is fully updated.

What should I do if the error keeps happening?

If the error persists after running system file repairs, check your recent hardware changes or software installations to see if they coincide with the start of the blue screen issues.

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