As you've found, there generally is no problem, but I've found a few such issues with flash drives as well.. Any opening or closing of folders or programs from the USB device will prevent it from being "released".. The only solution is to turn off the computer, then remove the device.
On a few machines, an update to the chipset driver of the BIOS version fixed the USB issue but not always..
Hope this helps.
Yeah, I know, I've read all the Google results about "open files" and
"locking handles" too, but bear with me and keep reading.
This is on a WinXP Pro SP3 desktop, current with all critical updates. I have a laptop HDD that I've installed in an external case for USB 2.0 connection to my PC. It connects to the PC as drive letter D:\. It works fine backing up my data until it comes time to disconnect it. Then, when I try to Safely Remove Hardware, I get the error msg in the topic title, along with "The device 'Initio 0M9AT00 USB Device' cannot be stopped because a program is still accessing it."
So I fire up Unlocker 1.9.0 and it says "No Locking handle found." Then I fire up Process Explorer v12.04 and Search for D:\ - I get the result "0 matching items."
So WinXP thinks some program is still accessing it, but what? I need some other ideas or tools to figure out what is going on. Up to this point, I've just been shutting down all open application programs and pulling the USB cable.
Oh, and one more interesting tidbit - when I connect this same HDD to my Win7 x64 laptop and click on safely remove hardware, Win7 releases the device properly and I can safely remove it. ***?!?
Thanks in advance for any help,