STATUS_FLOPPY_UNKNOWN_ERROR (0XC0000167) Fix on Windows 10/11

The 30-Second Fix: Disable the Phantom Floppy in Device Manager

What's actually happening here is that Windows still sees a floppy controller even though you don't have a physical floppy drive. This can happen after a BIOS update or a Windows feature update that re-enables the legacy floppy support. The error 0XC0000167 fires when some app (often an installer or old game) tries to talk to that controller and gets nothing back.

1. Press Win + X and select Device Manager.
2. Expand the Floppy drive controllers section. If you don't see it, skip to the next fix.
3. Right-click the listed floppy controller (usually Standard floppy disk controller) and select Disable device.
4. Reboot.

That's it. No driver reinstall, no registry edits. The controller is now off, and Windows won't try to access it. If the error disappears, you're done. If not, the system is still detecting a floppy drive somewhere — probably in the BIOS.

The 5-Minute Fix: Kill the Floppy Controller in BIOS

If Device Manager didn't have a floppy controller listed, then the hardware is being exposed by the motherboard's firmware. A lot of modern boards still ship with a legacy floppy controller enabled by default — even on Z790 and X670 chipsets. The error triggers when a program enumerates A: or B: drives and gets a timeout from the controller.

1. Reboot and enter BIOS/UEFI setup (usually Del, F2, or F10 during boot).
2. Look for Advanced > Onboard Devices or Peripherals.
3. Find a setting like Floppy Controller, Legacy Floppy Support, or Onboard Floppy Controller. Set it to Disabled.
4. Save and exit. Reboot into Windows.

The reason step 3 works is that the BIOS no longer exposes the floppy controller to the OS. Windows won't see any floppy hardware, so no driver loads, and no error fires. This is the real fix for most modern systems.

The 15+ Minute Fix: Purge the Floppy Driver and Registry Ghosts

If you still get the error after disabling the BIOS controller, there's a stale driver or a registry entry that's holding onto a phantom drive. This is rare but happens after a motherboard swap or a corrupt Windows upgrade from Windows 7 or 8.

1. Open Device Manager again. Go to View > Show hidden devices.
2. Expand Floppy drive controllers. If you see any grayed-out entries (ghost devices), right-click and Uninstall device. Check Delete the driver software for this device if available.
3. Now press Win + R, type regedit, and hit Enter. Back up your registry first: File > Export.
4. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\flpydisk. If it exists, delete the entire flpydisk key. This is the legacy floppy driver service.
5. Also check HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Fdc — that's the floppy controller driver. Delete it too.
6. Reboot.

After the reboot, Windows will not have any floppy driver loaded. The error 0XC0000167 requires a driver to be present and failing — with no driver, it can't fire. If you still see the error after this, the problem is in a specific application that's hardcoded to use A: or B:, or your BIOS has a hidden floppy emulation for legacy USB. Check BIOS for Legacy USB Support or USB Floppy Emulation and disable those too.

Note: Some Dell and HP business machines (OptiPlex 7080, EliteDesk 800 G6) have a BIOS setting called Legacy Floppy buried under System Configuration > Drives. It's often enabled by default even when no floppy is connected. That's the most common trigger on these brands.