ERROR_FLT_DO_NOT_DETACH (0X801F0010) Fix Guide

1. A Filter Driver Won't Let Go (Most Common)

This error pops up when you try to unmount a volume — like running diskpart with offline or detach vdisk — and a filter driver has locked onto it. The filter driver (often from backup software, antivirus, or encryption tools) is telling Windows "I'm not done yet."

The real fix is to identify that filter and remove its attachment cleanly. You don't need to restart. Here's the process:

1. Open Command Prompt as Administrator. Press Win, type cmd, right-click and pick "Run as administrator."
2. Type fltmc instances and hit Enter. This lists all filter driver instances attached to every volume. After pressing Enter, you'll see a table with columns like Volume, Filter, Instance, and Altitude.
3. Find the volume that's giving you trouble. Look for entries under the Volume column that match your drive letter (like C:) or volume GUID. The Filter column shows the driver name (e.g., Symantec, BackupFilter, VeeamFlt).
4. Once you spot the filter that's attached to your target volume, note its Instance name. Then run:
   

   fltmc detach <FilterName> <VolumeName>

   For example: fltmc detach Symantec C:. If you get an error about altitude, also specify the instance:
   

   fltmc detach Symantec C: <InstanceName>

   After running that, you should see "The operation completed successfully." No message means it worked.
5. Now try your original operation again — diskpart detach or unmount should succeed.

I've seen this most often with Veeam Backup & Replication, Acronis True Image, and Norton AntiVirus. Those backup apps love to hold onto volumes while scanning.

2. The WMI Provider Host Is Hanging

Sometimes the filter driver itself isn't the problem — it's the WMI Provider Host (WmiPrvSE.exe) that's stuck querying the filter. This happens when you use PowerShell or WMI commands like Get-WmiObject or wmic volume get and the query times out while holding a lock.

You'll notice this if the error appears after a PowerShell script runs or a WMI query completes. The fix is to restart the WMI service:

1. Open Services console. Press Win + R, type services.msc, hit Enter.
2. Scroll down to Windows Management Instrumentation. Right-click it and choose Restart. After a few seconds, the service will stop and start again. You'll see the status change from "Running" to blank and back to "Running."
3. Retry your volume operation. If it works now, the WMI host was your culprit.

This fix works best on Windows 10 version 21H2 and later, where WMI is more tightly integrated with filter management. If you're on Server 2016 or older, you might need a reboot after restarting the service.

3. Registry Corruption or Boot-Time Filter Loading

If neither of those works, the filter driver's registry entry is probably corrupt or the filter is set to load at boot and hasn't finished initializing. This is rare but I've seen it on systems that had an interrupted driver update.

Check the registry for the filter's entry and force removal:

1. Open Regedit as Administrator. Press Win + R, type regedit, right-click and pick "Run as administrator."
2. Go to:
   

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\FilterName

   Replace FilterName with the name you saw in fltmc instances output. If you didn't get a name, look under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\FltMgr\Instances for instance listings.
3. Inside the filter's key, find the Start value. If it's set to 0 (boot start), change it to 3 (manual) by double-clicking and entering 3. After clicking OK, the registry will save immediately.
4. Reboot the machine. After the restart, the filter won't load automatically. Run fltmc detach again to remove any remaining attachment.

Warning: If this filter belongs to antivirus or encryption software, disabling it at boot will leave you unprotected. Re-enable it after the operation by setting the Start value back to 0.

Quick-Reference Summary