"A driver can't load on this device": how to fix it in Windows 11 and 10

"A driver cannot load on this device" means Memory integrity in Windows Security refused a kernel driver it treats as vulnerable. Nothing is broken and Windows keeps working. Read the file name after Driver: in the window, then update or remove the program that installed it, and keep the protection on.

Facts checked on 15 October 2026. Steps written for Windows 11 (25H2 and 26H2) and Windows 10 22H2.

What "A driver can't load on this device" means in Windows 11 and Windows 10

The message comes from Program Compatibility Assistant, but the decision is made by Memory integrity in Windows Security. Microsoft says it appears because Memory integrity is preventing a driver from loading on your device. The driver is a .sys file that runs in the Windows kernel, the most protected part of the system.

Windows blocks it on purpose. The file is on the Microsoft vulnerable driver blocklist: drivers with known security flaws, drivers signed with certificates used for malware, or drivers that get around the Windows security model. Microsoft adds that such a driver is most likely not malicious in any way.

Title

A driver cannot load on this device

Driver line

Driver: followed by the file name, then the same name on its own line

Reason line, most PCs

A security setting is preventing this driver from loading. You'll need to adjust your settings to load this driver.

Reason line, some PCs

A security setting is detecting this as a vulnerable driver and blocking it from loading.

Buttons

Learn more, Close and a box Don't show this message again

Which setting

Memory integrity (also called HVCI) under Core isolation, with the Microsoft Vulnerable Driver Blocklist it enforces

Searches for the Microsoft page itself ("site:support.microsoft.com a driver can't load on this device") lead to a short note with two options: an updated driver, or Memory integrity off. This guide covers both, plus the safer steps in between that the note leaves out.

Why a driver cannot load on this device, from most to least common

Most often an old copy of a hardware tool is installed and starts with Windows: a CPU-Z or HWiNFO style monitor, a motherboard RGB or fan utility, an overclocking tool, or a game helper. Less often you use that tool and it is simply out of date. Rarely, the tool is gone but its driver entry stays, or the file came from somewhere unknown.

How to fix "A driver cannot load on this device" on Windows 11 and Windows 10

Start with Fix 1: it takes two minutes and tells you which program is behind the message. Fix 2 and Fix 3 end the message for most readers. Fix 6 and Fix 7 are for files that have no program behind them. Fix 8 lowers protection and is for one task only. You need an administrator account.

Fix 1. Read the window and find the program behind the driver

2 minutesNo riskEveryone. The window names the file, and the file points to the program you need to update or remove.

Microsoft says the driver name and company name in the notification are the only reliable details it has about the driver. Every other fix depends on knowing which program installed it.

1. When the window appears, write down the file name after Driver:, for example cpuz136_x64.sys.
2. Press Win + E, paste C:\Windows\System32\drivers into the address bar and press Enter.
3. Find the file, right-click it, choose Properties and open the Details tab.
4. Read File description, Product name, File version and Copyright: they name the maker.
5. If the file is not in that folder, search This PC for its name and note where it sits.

The number in a cpuz file name changes between CPU-Z releases, so cpuz136, cpuz146 and cpuz149 are the same family of driver from different versions. An old copy often comes with another program that bundles the detection code, not with CPU-Z itself.

Fix 2. Update the program that installed the driver

10 minutesLow riskReaders who use the program: a hardware monitor, a fan or RGB utility, an overclocking tool, a VPN or a game tool.

Microsoft's first advice is an updated and compatible driver from the driver maker. A current version of the program usually ships a newer driver that is not on the blocklist, and installing it replaces the old file.

1. Close the program, also from the notification area next to the clock.
2. Open the maker's own website and download the current version for Windows 11 or Windows 10. Use the maker's site, not a download portal.
3. Run the installer and let it replace the old version.
4. Restart the PC and sign in.
5. Open the program once and check that its sensors or controls work.

If the maker has no newer version, Microsoft suggests asking them whether a fix is coming. Until then, Fix 4 keeps the window away without lowering protection.

Fix 3. Uninstall the program you do not use

5 minutesLow riskReaders who do not use the program, or did not know it was on the PC. This is most readers with the message.

The driver only tries to load because a program or its service asks for it. Microsoft names removing the app that uses an incompatible driver as an option. When the program is gone, nothing asks for the file and the window stops.

1. Windows 11: open Settings > Apps > Installed apps. Windows 10: open Settings > Apps > Apps & features.
2. Type the maker or program name from Fix 1 into the search box above the list.
3. Select ... next to the entry and choose Uninstall, then accept the program's own uninstaller.
4. Restart the PC and sign in again.

Full steps for both Windows versions: Uninstall a program or app in Windows. Leave chipset, graphics, audio and network drivers alone unless Fix 1 points to them.

Fix 4. Stop the program from starting with Windows, or hide the notice

3 minutesNo riskReaders who want to keep the program installed for now, without the window at every sign-in.

The window appears when something at sign-in asks for the driver. If the program does not start on its own, nothing asks. Protection stays on, and only the features that need the old driver stay unavailable.

1. Windows 11: open Settings > Apps > Startup. Windows 10: press Ctrl + Shift + Esc and select the Startup tab in Task Manager.
2. Turn off the entry for the program you found in Fix 1.
3. Restart and sign in.
4. If the window still appears, tick Don't show this message again and select Close. That only hides the notice: the driver stays blocked.

Full steps: Stop apps from opening at startup.

Fix 5. Look for an updated driver in Windows Update and Device Manager

5 to 10 minutesNo riskReaders whose blocked file belongs to a device, such as a network card, a controller or a sound device, rather than a tool.

Microsoft names Windows Update and Device Manager as the places to look for an updated driver when this window appears. Device makers publish fixed drivers there, often as optional updates.

1. Windows 11: open Settings > Windows Update, select Check for updates, then Advanced options > Optional updates. Windows 10: Settings > Update & Security > Windows Update > View optional updates.
2. Expand Driver updates and tick only the entry for the maker named in Fix 1.
3. Select Download & install and restart if asked.
4. If nothing is offered, press Win + X, open Device Manager, right-click the device and choose Update driver > Search automatically for drivers.

More on Device Manager: Update, roll back or reinstall a driver.

Fix 6. Check where the file sits and scan it with Microsoft Defender

10 minutes for a quick scan, about 15 for an offline scanNo riskReaders who found no program that matches the file, or found the file outside the Windows drivers folder.

Old signed drivers are also brought onto PCs by attackers to reach the kernel, which is one reason Windows blocks them. A copy in C:\Windows\System32\drivers from a known maker is a leftover; a copy in a Temp or Downloads folder needs a scan.

1. Use the location you noted in Fix 1.
2. If the file sits in Temp, Downloads or an unknown program folder, open Windows Security > Virus & threat protection.
3. Select Scan options, choose Microsoft Defender Offline scan and select Scan now. The PC restarts for the scan.
4. After the restart, check Protection history for what Defender found.

Step by step: How to scan for malware with Microsoft Defender.

Fix 7. Remove a leftover driver entry with Autoruns

10 minutesRead the warningAdvanced readers who see the window although the program that installed the driver is gone.

An uninstaller can leave the driver's service entry behind, and Windows then tries to load the file at every start. Autoruns, a free Microsoft Sysinternals tool, lists every driver Windows tries to load and can delete that entry.

1. Download Autoruns from Microsoft's Sysinternals page on learn.microsoft.com and extract the ZIP file.
2. Right-click Autoruns64.exe, select Run as administrator, then Yes.
3. Open the Drivers tab and type the first letters of the file name, for example cpuz, into the filter box.
4. Check that the image path ends in the file the window named and the publisher matches Fix 1.
5. Right-click that entry, select Delete and confirm.
6. Restart the PC.

Fix 8. Only for one task: switch Memory integrity off, then straight back on

10 minutes plus two restartsRead the warningReaders who must run an old tool once and have no updated version. Not a fix for the message.

Microsoft names turning Memory integrity off as the option when no updated driver exists. While it is off, the flawed driver loads and any program could misuse it, so the protection must be on again as soon as the task is done.

1. Windows 11: open Settings > Privacy & security > Windows Security > Device security and select Core isolation details. Windows 10: Settings > Update & Security > Windows Security > Device security > Core isolation details.
2. Set Memory integrity to Off. If the page also shows a Microsoft Vulnerable Driver Blocklist switch, set it to Off too.
3. Restart, run the old tool and finish the one task.
4. Uninstall the tool again (Fix 3).
5. Go back to Core isolation details, set both switches to On and restart.

The window still appears: what to check and what to send support

The window itself is the best log: it names the file Windows blocked. If it now names a different file, a second program has the same problem, and the same steps apply to that file and its maker.

• Memory integrity will not turn on: Windows says an incompatible driver is installed. Check with the maker for an updated driver, or remove the device or app that uses it.
• A device stopped working after Fix 3: the uninstaller removed a driver the device needs. Install the plain driver from the PC or device maker's support page.
• The file keeps returning in a Temp folder: something on the PC drops it there. Run a Microsoft Defender Offline scan as in Fix 6 and treat it as a security incident.
• The Memory integrity switch is greyed out: an organisation manages the PC, or hardware virtualization is off in UEFI or BIOS. That is not caused by the blocked driver.

Keep "A driver cannot load on this device" from coming back

Microsoft adds drivers to the blocklist every quarter, so a tool that works today can be blocked later. Windows 10 left support on 14 October 2025, and a PC that stays on Windows 10 no longer gets those updates.

Frequently asked questions

What does "A driver cannot load on this device" mean?

It means Memory integrity in Windows Security blocked a kernel driver because it is on Microsoft's vulnerable driver blocklist. The driver has a known flaw, was signed with a certificate used for malware, or gets around Windows security. Microsoft says the blocked driver is most likely not malicious. Windows keeps working; only the program that needs the driver loses some features, such as sensor readings or fan control.

How do I fix "A driver cannot load on this device" on Windows 11?

Note the file name after Driver: in the window and find the program it belongs to (Fix 1). Update that program from its maker's site (Fix 2) or uninstall it if you do not use it (Fix 3), then restart. That ends the message for most people. Keep Memory integrity on: the block is deliberate. The Windows 11 path to the setting is Settings > Privacy & security > Windows Security > Device security.

What does "A security setting is preventing this driver from loading" mean?

It is the second line of the same window, and the security setting is Memory integrity. The full line reads: "A security setting is preventing this driver from loading. You'll need to adjust your settings to load this driver." Adjusting the setting means turning Memory integrity off, which Microsoft lists only as a last option. Updating or removing the program behind the driver is the safer way to stop the message.

What is cpuz136_x64.sys and why can it not load?

The name points to the kernel driver of CPU-Z by CPUID, which reads processor and memory details. The number changes between versions, so cpuz146_x64.sys and cpuz149_x64.sys belong to the same family. Old copies are blocked as vulnerable. They often come with another program that bundles CPU-Z's detection, not with CPU-Z itself. Read the company name in the window, then update or remove that program (Fix 2 or Fix 3).

Can I just close the window and ignore it?

Yes. The message is Windows protecting you, not a fault, and the PC keeps working as before. Only the program that wanted the driver loses the features that need it. If the window bothers you at every sign-in, removing the unused program (Fix 3) is cleaner than ticking Don't show this message again, which only hides the notice.

Should I turn Memory integrity off?

No, not to silence this message. Memory integrity makes it hard for malicious programs to use low-level drivers to take over the PC, and it is what stops the flawed driver from being misused. Updating or removing the program takes a few minutes and keeps the protection. If you must run an old tool once, follow Fix 8 and turn the protection back on right after.

Why did the message start after a Windows update?

Microsoft updates the vulnerable driver blocklist every quarter and ships it with the monthly Windows updates. Since the Windows 11 2022 update the blocklist is on by default. So a driver that loaded for years can be blocked after a normal update. Uninstalling the update does not help: the block returns with the next one, and you lose security fixes.

What are vmdrv.sys, mslo64.sys, atillk64.sys and pcdsrvc_x64?

They are other drivers readers see in the same window. We could not confirm their makers from an official source, so do not trust a name guess. Read the company name in the window and the Details tab of the file (Fix 1), then update or remove that maker's program. If no program matches and the file sits outside the Windows drivers folder, scan it (Fix 6).

Is the blocked driver a virus?

Usually not. Microsoft says a driver blocked this way is most likely not malicious. The risk is that other programs can misuse its flaw to reach the Windows kernel, and attackers have carried such old signed drivers onto PCs for that reason. A copy in C:\Windows\System32\drivers from a known maker is a leftover. A copy in a Temp or Downloads folder is a reason to scan at once (Fix 6).