Yesterday I received my shiny Samsung M3 1TB Portable Hard Drive from Amazon to solve my storage problems (I hoard MP3s). It looks like this:
A static picture does little justice to the case. It’s not covered by a tacky plaid pattern; the surface is all angular. You should see the light reflects beautifully when you wobble it about.
Today I plugged it in to my workstation to transfer a few personal downloads. When I had finished, I played the responsible user and safely disconnected the device before yanking the USB cable from the socket.
In Windows 7, you do that by context-clicking the system tray icon that looks like a USB connector and choosing ‘Eject Samsung M3 Portable’ or whatever matches the name of your device:
Instead of rewarding me with a signal that I could now yank my device from the socket, Windows gave an impudent error dialog that declares “This device is currently in use”:
The dialog indirectly warns me that I could potentially trash data by ejecting the device prematurely. However, the proposed resolution to “Close any programs or windows that might be using the device, and then try again.” is vague, and that sucks.
I multitask a lot at my workstation, and have open files all over the place. I don’t feel like wading through each window to find the one that won’t let go.
Thankfully, you can make up for the dialog’s shortcomings with Mark Russinovich’s awesome Handle utility. The following steps assume you have put handle.exe in your Windows folder so that it is on the path.
Start a new PowerShell session and use handle to search for processes that have a file open anywhere on the device. For me, the root directory of my device is I:\, so the command and output look like this:
After the copyright notice, each line of output represents a file handle – a process that has opened a file.
The last line of output is the useful one here. It means that the file I:\Iain Elder.docx, a copy of my CV, is open in Microsoft Word, whose executable name is WINWORD.EXE.
Make sure you’re finished working with the file (I have) and then close the file. I’ve got no other documents open in Word, so I can just close Word from the task bar like this:
Go back to the PowerShell session and repeat the previous command. You should see one less line of output:
The handle output now shows that only Windows’ internal System process has opened files on the device. I’m not sure what the files in I:\$Extend\$RmMetadata are for, but they looks like something important to Windows.
If your output shows more lines than this, then continue to close files until only the System process holds open files.
If you try eject the device again, you should see a popup indicating successful removal like this:
You can now safely yank the cable!
A problem with the solution
Sometimes, even though the System process is the only one holding opening files, you will still see the error dialog when you try to eject the device.
Right now the same handle command produces similar output, but it shows that the System process now also has a handle on the root directory of the device:
The System is greedily and unjustifiably hogging my device. I want it back, even if I have to kill the System process to do that.
The System process starts before I get to control the computer, so it’s not really mine to kill. We can be kinder by using handle to break its fingers instead of killing it outright.
The handle utility lets you close a file handle by force if you give it a couple of magic numbers. In each line of output, the number after pid: is the ID of the process, and the number before the file location is the ID of the handle.
From the above output, you can close the file handle of the System process on the root directory of the device using handle like this:
Because forcing a file handle to close is a potentially dangerous operation, handle asks you to confirm the action before committing it.
I’m feeling lucky, so I press y then return. The remaining output looks like this:
I tried the close-and-reopen-Explorer workaround on TechArena. It didn’t affect the output of handle and I still can’t eject my device.
I tried searching for services as suggested on Talking Technical, but I couldn’t find any.
I don’t have time left to try anything else.The only thing left to do for now is to shut down the computer before removing the drive.
Kinda defeats the purpose of having a removable drive, eh?