Fix Driver Unloaded Without Cancelling Pending Ops (2026)

I remember the first time I saw the "Driver Unloaded Without Cancelling Pending Operations" stop code. It was 2: AM, my build machine was stuck in a reboot loop, and my unsaved work was vanishing like smoke. The screen glared with that specific error, threatening data loss if I forced a shutdown. It’s a frustrating error that strikes fear in the hearts of both developers and casual gamers.

But here is the good news: this isn’t just a generic "reboot and pray" situation. This specific kernel warning usually points to a precise conflict—often involving third-party security agents like FortiClient, anti-cheat frameworks like Easy Anti-Cheat (EAC), or recent Windows 11 updates that have tightened driver signature enforcement. In this guide, we move away from generic advice. Instead, we use a structured decision-tree approach. We’ll dig into why the I/O scheduler is hanging, how to safely unload drivers without corrupting your filesystem, and how to identify the exact .sys file causing the chaos.

Understanding the Mechanism: Why Drivers Fail to Unload Safely

Before we jump into fixes, you need to understand why Windows is panicking. When a driver unloads, it has to clean up its mess. It needs to cancel any pending I/O requests (reads/writes to the disk or network) and release memory resources. If it doesn’t, the system is left in an inconsistent state.

Decoding Arg1 and Arg2 in the Stop Code

If you look at the crash dump or the details of the BSOD, you’ll see parameters like Arg1 and Arg2. This is where most generic guides go silent. I’ve spent years analyzing these logs, and I can tell you that these arguments are your map.

Arg1 typically points to the driver object that failed to unload. Arg2 often indicates the state of the I/O stack at the time of failure. It’s not always a binary "hardware bad, software good" situation. In my experience, a "pending operation" usually signals a timing issue in the software layer rather than a physical failure of the disk itself.

Think of it like a busy restaurant kitchen. The chef (the driver) is trying to leave the restaurant (unload), but they still have three plates in the oven (pending I/Os). If they just walk out the door without removing the plates, the oven burns down. The "kernel module pending operations warning" is the smoke alarm. It’s telling you that the cleanup sequence was interrupted. This is fixable, but you have to address the source of the interruption, not just the smoke.

The Role of I/O Scheduler Latency in Pending Ops

Why do operations remain "pending"? This brings us to the concept of I/O scheduler latency. Windows doesn’t just write data to your NVMe or HDD instantly; it buffers it. The write-back cache allows for faster system responsiveness, but it creates a window where data exists in RAM but not yet on the physical drive.

If a driver unloads while this cache is dirty—meaning there are uncommitted writes—the system has to ensure data integrity. It attempts to flush these buffers. If the flush times out or if a dependent process is blocking the I/O path, the driver hangs. This is why you might see this error after heavy file operations, like installing large updates or running intensive database transactions. The filesystem flush requirements are strict. If the driver doesn’t wait for the SYNC command to complete, the OS triggers the stop code to prevent filesystem corruption.

Scenario-Based Troubleshooting: Gaming, Security & Windows 11

Now that we know the how, let’s look at the who. Who is causing the driver to fail? In 2026, the landscape is dominated by three culprits: gaming anti-cheats, enterprise security software, and the ever-evolving Windows 11 update cycle.

Resolving Conflicts with Easy Anti Cheat (EAC) & Valorant

If you’re a gamer, listen up. Easy Anti-Cheat (EAC) is a frequent offender. It uses kernel-mode drivers (vGk.sys or vge.sys) that hook deeply into the system. I’ve seen countless cases on Steam forums where an outdated EAC version conflicts with a new Windows 11 kernel update.

When this happens, the EAC driver tries to unload, but it’s still monitoring a process that is actively writing to disk (maybe the game client is downloading assets in the background). The result? A BSOD loop.

To fix this:

1. Boot into Safe Mode. This is crucial because Safe Mode does not load EAC.
2. Uninstall the Game and EAC Components. Don’t just update the game. Go into Control Panel > Programs and fully remove the anti-cheat service.
3. Registry Clean-up. Sometimes, residual entries in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services keep the driver trying to start. Use a tool like Sysinternals Autoruns to find and disable any remaining EAC startup entries.
4. Reinstall. Download the latest version of the game and let it pull the updated EAC framework.

Handling Enterprise Security Software (FortiClient & Others)

For IT professionals and corporate users, FortiClient and similar endpoint protection agents are the bane of existence. These agents install root-level drivers to monitor network traffic and file access. The problem is that these vendors often release driver updates out of sync with Microsoft’s rapid patch cycles.

I once worked with a client where FortiClient’s ftnfd.sys driver was conflicting with a specific KB update. The driver would attempt to initialize before the storage stack was ready, leading to pending I/O errors that never cleared.

How to mitigate:

• Check Vendor Compatibility Lists. Before applying major Windows 11 cumulative updates (like the KB5051987 context mentioned in recent community reports), check your security vendor’s release notes.
• Temporary Disablement. If you have admin rights, use the vendor’s administrative console to pause the agent’s real-time scanning. This stops the high-volume I/O monitoring that often clogs the queue.
• Update the Agent, Not Just the OS. Often, the fix isn’t a Windows patch; it’s a driver update from the security vendor to support the new Windows kernel.

Windows 11 Specific Updates & Driver Signature Enforcement

This is where it gets tricky for power users and modders. Starting with the late 2024/early 2025 updates, Microsoft has aggressively enforced driver signature enforcement. If you are running unsigned drivers—perhaps for a custom SSD controller, a modified GPU fan curve utility, or a kernel-level cheat—Windows 11 will now block them or force an unload that fails, triggering our error.

To test if signature enforcement is the root cause:

1. Open an elevated Command Prompt.
2. Run: bcdedit /set nointegritychecks on
3. Reboot.

If the BSOD stops, you’ve confirmed that an unsigned driver is being blocked. However, keep in mind that this is a temporary diagnostic switch. Do not leave this setting on permanently, as it leaves your system vulnerable to malicious drivers. You need to find the specific .sys file, get it signed (or find a signed alternative), and then revert with bcdedit /set nointegritychecks off.

Note: Windows 10 and 11 handle these repair paths slightly differently. On 11, the recovery environment is more isolated. If you are stuck in a boot loop, use the "3 power cycles" method (force shut down during boot logo, three times) to access the Recovery Environment (RE) directly from the hardware.

Advanced Diagnostics: Locating the Faulty .sys File

If you’ve tried the scenario-based fixes above and the error persists, we need to get granular. We need to find the exact driver file that is misbehaving.

Using Device Manager & SFC/DISM for Root Cause Analysis

Before diving into hex editors, let’s clean up the system files. Corrupted system files can confuse the driver stack.

1. SFC Scan: Run sfc /scannow in an elevated prompt. This checks for corruption in protected system files.
2. DISM Repair: If SFC fails or doesn't find anything, run DISM /Online /Cleanup-Image /RestoreHealth. This resets the Windows image component store.

Next, open Device Manager.

• Click View > Show hidden devices.
• Look for any devices with a dotted-line icon. These are "phantom" drivers—hardware that was removed but whose drivers are still lingering in the registry.
• Right-click and uninstall any suspicious drivers, especially those marked as "non-plugin" or "unknown".

Analyzing Crash Dumps for Hardware vs. Software Issues

This is where the real detective work happens. You need to open your most recent crash dump (.dmp file) using WinDbg (available for free from Microsoft).

When the dump loads, run !analyze -v.

• Look at "FAULTING_MODULE": This will tell you which driver crashed. If it’s nvpcf.sys (NVIDIA) or vge.sys (EAC), you know your enemy.
• Check for Memory Issues: If the dump analysis suggests MEMORY_MANAGEMENT errors alongside the driver unload, start suspecting your RAM. Run mdsched.exe (Windows Memory Diagnostic) to rule out bad sticks.
• GPU vs. CPU: If the faulting module is related to your graphics card, the "pending operations" might be VRAM writes that didn’t flush. This is a common issue with aggressive overclocking.

In my experience, 80% of these "mysterious" driver unload errors are actually just a mismatched driver version. The other 20% are hardware degrading.

Safe Unload Procedures & Prevention Best Practices

Prevention is better than a 3 AM BSOD. How do we ensure drivers unload safely?

Preventing Data Loss During Forced Removals

If you are a developer or power user who manually unloads drivers or hot-swaps storage devices, you must respect the SYNC command.

• For USB/NVMe Removals: Always use the "Safely Remove Hardware" tray icon. This tells the OS to flush all pending writes to the cache before powering down the device.
• Command Line Safety: If you are scripting driver removals, never just delete the .sys file while the service is running. Use sc stop [ServiceName] and wait for the service to fully terminate. Check the PendingOps queue in the Event Viewer (System Log) for any lingering warnings before proceeding.
• Checklist: Before any major driver surgery, back up your C:\Windows\System32\drivers folder. Yes, it’s a big backup. It’s worth it.

Automating Recovery: Windows RE & System Restore

If you are stuck in a boot loop, your best friend is Windows Recovery Environment (RE).

1. Access RE: Hold down the power button to force a shutdown during boot. Repeat this 3 times. Windows should detect the failure and auto-launch RE.
2. System Restore: Navigate to Troubleshoot > Advanced Options > System Restore.
3. Roll Back: Select a restore point from before the driver installation or the Windows update.

System Restore is often overlooked because people think it’s just for "going back to yesterday." But it rolls back driver registry keys and system files effectively. If a clean install is your only option, use the "Keep My Files" option to preserve your data while resetting the OS.

FAQ

Is it safe to ignore the 'Driver Unloaded Without Cancelling Pending Operations' warning?

No. This error indicates that the system is in an inconsistent state. Ignoring it risks data corruption, particularly in active databases or during large file transfers. While a single occurrence might be benign (e.g., a slow drive), a recurring error is a clear sign of instability that will eventually lead to permanent data loss or hardware failure.

How can I check if there are active I/O operations on a specific block device?

You can use Resource Monitor in Windows. Open it by typing resmon in the Run dialog, go to the Disk tab, and look at the "Active" column. It shows which processes have open handles on specific drives. For a deeper dive, use Sysinternals Handle.exe to list all open handles on a specific .sys driver or disk device.

Does this error indicate hardware failure or just a software timing issue?

In most cases, it is a software timing issue caused by a driver bug or conflict. However, if you see this error consistently on a specific drive (e.g., always nvme0 or disk1), it strongly suggests failing hardware. Run chkdsk /f on that drive. If the error persists even after replacing the driver, suspect the physical media or controller.

How do I force a file system to sync all pending writes before unmounting?

In Windows, you don’t typically "unmount" NTFS volumes manually unless you are in a specialized environment. However, you can force a flush by running fsutil volume dirty (with caution) or simply ensuring the "Safely Remove Hardware" process completes. For developers, issuing an IOCTL_FLUSH_BUFFERS command to the driver ensures the cache is written to disk before the driver is unloaded.

Conclusion

The "Driver Unloaded Without Cancelling Pending Operations" error is less of a mystery and more of a communication breakdown between your hardware, your kernel, and your third-party software. It’s not always a catastrophic failure.

The Decision Tree:

1. Identify the Source: Did it start after a game update? A Windows patch? An enterprise security agent install?
2. Apply Specific Fix: Uninstall/reinstall EAC, update FortiClient, or check driver signatures.
3. Run Advanced Diagnostics: Use WinDbg to isolate the .sys file.
4. Recover: Use System Restore or Safe Mode to stabilize the system.

If you are still stuck, don’t hesitate to share the specific .sys file name from your crash dump in the comments below. I can often tell you immediately if it’s a known conflict with a 2026 driver update. Let’s get your system stable again.