Diagnosing Valorant VAN 9003 Secure Boot Failure on Windows 11 25H2 After May Update

Symptoms

• Valorant fails to launch with VAN 9003 error code.
• Secure Boot status reported as disabled or failed in system logs.
• Windows Defender System Guard runtime reports integrity violations.
• No recent hardware or firmware changes preceding the error.

Likely causes

• Windows 11 25H2 May update resetting or disabling Secure Boot settings in UEFI firmware.
• Incompatibility or corruption of Riot Vanguard anti-cheat driver (vgk.sys) after update.
• System integrity checks failing due to altered Secure Boot keys or TPM state.
• Conflicts between Windows Secure Boot policies and Valorant's anti-cheat requirements.

What FixWin checks

• Check Secure Boot status via System Information (msinfo32) under 'Secure Boot State'.
• Verify Vanguard driver (vgk.sys) is loaded and running with correct signature.
• Review Windows Event Logs (System and Security) for Secure Boot or driver errors.
• Inspect TPM management console (tpm.msc) for errors or disabled state.
• Confirm Windows Boot Manager settings in UEFI firmware are intact and Secure Boot enabled.

AI diagnostic workflow

• Open System Information (msinfo32) and confirm Secure Boot State is 'On'.
• Launch Event Viewer and filter for Kernel-Boot and CodeIntegrity logs around update installation date.
• Run 'sc query vgk' in elevated Command Prompt to check Vanguard driver service status.
• Access UEFI firmware settings during boot to verify Secure Boot is enabled and keys are valid.
• Use 'tpm.msc' to confirm TPM is enabled and operational without errors.

Related Windows entities

• Secure Boot component
  Ensures system boots using only trusted software, required by Vanguard anti-cheat for Valorant.
• vgk.sys (Riot Vanguard Kernel Driver) driver
  Kernel-level anti-cheat driver that requires Secure Boot and system integrity to function properly.
• System Event Log log
  Contains error and warning entries related to Secure Boot failures and driver load issues.
• TPM (Trusted Platform Module) component
  Works with Secure Boot to provide hardware-based security and system integrity validation.
• Windows Defender System Guard Runtime service
  Monitors system integrity and reports violations that can cause anti-cheat failures.

Repair logic

Since Valorant's VAN 9003 error after the Windows 11 25H2 May update is primarily caused by Secure Boot being disabled or failing system integrity checks, the diagnostic steps focus on verifying Secure Boot status, Vanguard driver integrity, TPM state, and relevant system logs. Repair involves re-enabling Secure Boot in UEFI firmware, ensuring Vanguard driver is properly signed and loaded, and confirming TPM is active. Diagnosing these components helps isolate whether the issue is firmware-related, driver corruption, or system integrity enforcement failure.

FAQ

Why does Valorant show VAN 9003 error after the Windows 11 May update?

The May update can reset or disable Secure Boot settings in UEFI firmware or cause Vanguard's kernel driver to fail signature verification, leading to VAN 9003 errors.

How can I check if Secure Boot is enabled on Windows 11?

Open System Information (msinfo32) and look for 'Secure Boot State'; it should read 'On' if enabled.

Is it safe to disable Secure Boot to fix the VAN 9003 error?

Disabling Secure Boot is not recommended as Valorant's anti-cheat requires it for security; instead, re-enable Secure Boot and ensure all related drivers and firmware settings are correct.

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