@Fixer -
Have you tried in Safe Mode?
Seems that a process is hanging on to the drive.
What's strange is that a reboot doesn't solve the problem.
You could go into Device Manager and re-PNP the USB Root Hub.
Just leave the keyboard and mouse attached if you do this.
All other USB devices should be detached. Then reboot.
Install one device at a time and check.
Do the USB Mass Storage devices last.
So just for fun, I tried to eject the Verbatim usb stick I was using in my previous post. I closed everything that was connected with the stick during this past episode, requested to eject and yet it still refused, throwing out the usual warning (1).
After enabling the quick release feature in properties I received a restart required notification (2). I played along and after the restart it complied with my request to eject, done.
I'm familiar with this process (too much so :-/) but I wanted to run through the process for demonstration purposes and I do know, I own at least one device that refuses to eject regardless of the settings, I thought it was this Verbatim thing.
Last edited by W10 Tweaker; 16 May 2020 at 07:00.
The quote in #10 answers both points.
- - - Updated - - -
I currently have a SanDisk Ultra plugged in, it always gives the warning. Rebooting doesn't change it, neither does just waiting and trying again. Thanks for all the interest guys but I'm off to bed. Some things you just have to live with.
What Tweaker recommended is correct. You don't need for any I/O's to that device to complete. Windows will not terminate the job until the last write is complete. But you end up losing any additional performance where buffer writes buffer writes a completed before they are actually written to the device. This makes any program run seemly faster, because they can complete before the I/O operation has actually completed. I have a USB 3.1 external drive running in Raid 1. They are spinners, and there are 2 of them. Performance is not what you would call fast for USB 3.1, but running that device with buffering option, will complete 3-5 minutes before data is all written to to. Now removing that drive while its writing to the device will lose the data that hasn't been written.
The choice is run at normal read/write speed, and be able to just remove the external unit when the job ends. Run it buffered don't worry about it, get done quicker and windows won't release the unit until its really completed. Just wait.
But remember if your running a command window, Task Manager etc. that unit will be locked up for the duration, whether either of these systems are using that device or not when buffering is enabled.
Another usual suspect here can be your AV program (even Windows Defender). Or you could try doing a chkdsk /f on that usb stick to see if there is some issues preventing proper operation and ejecting.
That all sounds perfectly logical, but doesn't explain this - hours ago I inserted a blank, formatted 30Gb pen drive and I haven't accessed or tried to use it since. However it cannot be ejected.
- - - Updated - - -
EDIT - chkdsk e: /f says it's good.
- - - Updated - - -
EDIT - I've always ejected USB drives by clicking the Safely Remove Hardware and Eject Media button in the notification area of the taskbar and invariably get the This Device is Currently in Use message. This morning it occurred to me to try to eject the drive by right clicking it in File Explorer. Bingo - no message, drive disconnected.
So it's simply been Explorer hanging on to the drive and I'm sorry I've had you all scratching your heads over it.
Quote
