USB drive unable to safely remove on Windows

[JSchoeck]

With a newly installed BTRFS 1.7.5 driver on current Windows 10, I have the problem that I cannot remove the USB drive via Windows' "safely remove drive" function in the task bar. The error message is (translated from German): "The device 'Volume' cannot be stopped, because a program is accessing it. Close all programs which might use the device and repeat the process." - titled "Error when unmounting 'USB-connected SCSI (UAS)-..."

I am not using any programs that access the device. I only checked out the content of some folders, not even opening a file - and even closing the Explorer window didn't allow me to remove the drive. This has happened every time I tried over the last days.

As far as I know there is also no other way to remove / unmount a drive in Windows, also no in the btrfs properties of the mounted volume.

[maharmstone]

Thanks. I suspect this is the same issue as https://github.com/maharmstone/btrfs/issues/297, namely something is grabbing the drive and not letting go.

If you log out and log back in again, will it let you unmount then?

[resadent]

I can confirm I can't umount the device even after loging out and back in again.

[Hiltronix]

Hello,

I'm having the same issue with Windows 7 64, with WinBtrfs v1.7.6. Not able to eject external drive using taskbar drive eject feature.

Problem Ejecting USB Mass Storage Device Windows can't stop your 'Generic volume' device because a program is still using it. Close any programs that might be using the device, and then try again later.

This even happens right after Windows startup, and not opening any apps or an Explorer window. I'm not able to eject drive cleanly.

[jonau01]

Same issue with btrfs-1.7.8.1 on Windows 10 20H2.

[IlluminatiWave]

Same error, any btrfs drive trying to disconnect, freezes the system

WinBtrfs 1.7.8.1 (Installed with Chocolatey)

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Windows 11 Enterprise Version 21H2 OS Build 22000.176 Windows Features Experience Pack 1000.22000.176.0

[techno156]

It could be a Windows issue. It seems similar to problems that I encountered when ejecting an NTFS device (where $LogFile, or similar NTFS Metadata handle remains active, and prevents Windows from ejecting the drive)

I managed to eject the BTRFS device by firing up diskpart, selecting and offlining the disk, and then using the safely remove feature, in the same way that I would do with an NTFS device.

Offlining the disk does not appear to keep the drive offline if it is reconnected, so there is also no need to online the drive immediately afterward.

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Version: WinBtrfs 1.7.9 (Installed with Chocolatey) Windows 10 Home Edition (x64) 21H1 Secure Boot Enabled

[jazir555]

Same problem here on the newest version

[1n5aN1aC]

Same for me.

I was able to eject using diskpart for some reason......

EDIT: All changes I made on Windows was rolled back. Steps I did: Connect drive. Copy ~3GB in 30 files onto the drive. Wait about a minute to let things settle. Attempt to safely remove a few times. Then Eject via diskpart. Upon plugging into a Linux system, drive was exactly the same as it was before being plugged into Windows.

[Gspin96]

I'm getting this issue as well on windows 10. Additionally, unplugging the device that wasn't successfully expelled resulted in BSOD. My first attempt at ejecting via diskpart worked, second attempt resulted in BSOD as soon as the command was entered.

[user050126]

Perhaps try to check what process holds the resources: https://superuser.com/questions/87364/can-windows-tell-me-what-is-using-my-usb-drive (look for "Native Method" within the thread).

[megapro17]

It still not possible to eject any drive

[Masamune3210]

What process does Event Viewer blame for holding the lock preventing the eject?