Fix “Driver Blocked Due to Security Policy” on Windows 10/11

Quick answer

Open Windows Security > Device Security > Core Isolation > Memory Integrity. If it's on, turn it off and restart. If the driver still won't load, run verifier /query to find the driver and remove it from the block list via group policy or registry.

Why this error happens

Windows 10 and 11 enforce driver signing and integrity through a few overlapping mechanisms. The most common trigger is Memory Integrity (also called Hypervisor-protected Code Integrity, or HVCI). When this is enabled, any driver that doesn't meet Microsoft's HVCI requirements — usually older drivers, unsigned ones, or those with known vulnerabilities — gets blocked before it can load. You'll see the error in the system event log under Event ID 3033 with the message "The driver X was blocked due to security policy."

I remember dealing with this on a client's Dell Precision running Windows 11 22H2 — a legacy fingerprint scanner driver (v7.xx from 2018) triggered it. You'll also see this with VPN clients (Pulse Secure, some older OpenVPN TAP drivers), antivirus filter drivers, and audio drivers from 2015-era hardware. The error isn't malware itself — it's Windows being overprotective.

Three things can cause it: HVCI/Memory Integrity, Driver Signature Enforcement (less common now), and Group Policy blocks (enterprise deployments). Let's fix each.

Step-by-step fix

Step 1: Turn off Memory Integrity (HVCI)

1. Press Win + I to open Settings.
2. Go to Privacy & Security > Windows Security > Device Security.
3. Click Core Isolation details.
4. Toggle Memory Integrity to Off.
5. Restart your PC.

If the driver loads after reboot, you're done. But here's the thing: Microsoft recommends keeping Memory Integrity on for security. If you need the driver, check the manufacturer's website for an updated driver signed for HVCI. Most hardware vendors released compatible versions by mid-2020.

Step 2: Check Group Policy (Pro/Enterprise editions)

If Memory Integrity was already off, group policy might be blocking the driver. Run gpedit.msc and go to Computer Configuration > Administrative Templates > System > Driver Installation. Look for Allow Installation of devices that match any of these device IDs — if it's configured, your driver might be on the deny list. You can also check Code Integrity policies under Windows Components > Windows Defender Application Guard. Disable any restrictive policy, then restart.

Step 3: Remove the driver from the block list via registry

This is for advanced users. Open regedit and go to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\DeviceGuard\Scenarios\HypervisorEnforcedCodeIntegrity\AllowedPolicySigners

If you see a key named after your driver's publisher, delete it. Also check:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CI\Policy\Blocked

Remove any entries matching the driver's SHA256 hash or filename. Back up the registry first — I've seen people delete the wrong keys and brick driver loading completely.

Step 4: Disable Driver Signature Enforcement (temporary)

1. Hold Shift while clicking Restart in the Start menu.
2. Troubleshoot > Advanced options > Startup Settings > Restart.
3. Press 7 to disable driver signature enforcement.
4. Install the driver while in this mode.

This only lasts until the next reboot. It's a workaround, not a fix — but it tells you if the driver itself works.

Alternative fixes if the driver still won't load

• Update the driver: Go to Device Manager, right-click the device, choose Update driver > Browse my computer > Let me pick. Select a compatible driver from the list — sometimes a Microsoft-provided generic driver works.
• Use Windows Update: Sometimes the block gets lifted by a cumulative update. Run wuauclt /detectnow from an admin command prompt.
• Check for third-party security software: Some antivirus tools (McAfee, Norton) add their own driver restrictions. Temporarily disable them and test.
• System Restore: If the error appeared after a Windows update, roll back with rstrui.exe.

Prevention tip

Keep all drivers on the Windows Hardware Compatible List (HCL) and signed with an EV certificate. Avoid drivers from 2018 or earlier for critical devices. If you must use an older driver, disable Memory Integrity, but that's a security trade-off — do it only for hardware that's air-gapped or in a limited-use environment. I tell clients: update the hardware if possible. A $30 NIC is cheaper than the headache.

Real-world example: A factory with Windows 11 IoT Enterprise. Their barcode scanner driver from 2016 triggered this error. We had to disable HVCI via group policy because the vendor went out of business. Not ideal, but it worked.