I've always had this problem with one of my Toshiba external drives. I value that drive really high because of its built-in shock detector, what is currently very hard to find. But the cannot-remove-it-safely issue was driving me crazy.
Today, I've hit this question/thread on social-technet MS site. While there's a lot of noise down there, they point out a few common issues. Like the Distributed-Tracking service. It's actually hard to read through it all due to some cohones-size-flame-war that escalated at some point, but reading the topic from its end helps;)
Anyways, sorry for my chatty mood, I've just fixed my case permanently.
I've got any Distributed-Tracking/Windows-Search/etc services off and was still unable to safely-unplug the drive. Someone somewhere suggested that "quick removal" is the culprit, but almost all my USB drives run on it and I still can remove them safely.
However, I actually tried switching this drive to "high performance mode" and .. it caused the TxfLogContainerXXXX handles to evaporate. So, it's true that this is the quick-removal option. However, this did not released my drive yet. Still couldn't eject it.
Then I have went to ComputerManagement->DriveManagement utility and I have removed any drive-letter assignements for that drive. Instantly afterwards, I was able to eject the drive.
Then I tried connecting it again, reassigning the drive letter, switching it to quick-removal and it seems to work properly and still be ejectable.
On the so-long topic on MS site, they also mention these actions. Someone suggested to:
- change drive letters and reboot
- or, try turning the drive "offline"
I think that the "turn the drive offline" via "computer management -> drive management" might actually be the quickest solution, however I have not tried it since my random attempts helped before I've read about that.
That’s because Windows, to improve performance, uses a technique called "deferred writes" wherein Windows doesn’t always immediately write everything to your external drive each time you use it. Rather, it consolidates lots of small writes into one big write by holding the data in memory.
It’s just like washing the dishes; it’s far more efficient to do one dishwasher load per day than do a load each time you use a single cup or plate.
But the downside is that some of the data you think you transferred to your USB drive may actually still be in your computer’s memory. That’s why you shouldn’t just pull the drive out but first use the Safely Remove Hardware icon to force Windows to write to the drive anything it is holding in memory.
That’s easy enough to say, but the Windows "Safely Remove Hardware" feature is confusing to use, particularly if you have several USB devices. Worse still, the icon often goes missing from the system tray.
For Faster remove you can change your USB disk Setting to protect Mode. but in this mode transfer is slower.
But other way is using "usb-disk-ejector" this Software is Free and portable. fast and safe.
Best Answer
It's still necessary unless you can always make sure there are no unsaved changes to files on the drive.
"Quick removal" disables write caching so you can be sure that the file system won't be damaged due to important changes being delayed by the cache, but it can't magically make all programs automatically save every change to files on the drive as you make it. If you unplug the disk when there are open handles that was used for writing, depending on the parameters used when the handles are created, you may lose the entire unsaved file or the part that was still in the program's buffer.
In this sense, it's more useful of save often than using quick removal (as most decent programs will flush the cache when they save anyway).
Edit:
If you select "Better performance", not only user data go through the device's cache, so will file system operations. If you unplug or suffer a power loss before a file system operation in the cache is written to the physical media, you get an inconsistent file system. Depending on how robust the FS is and whether it accounts for this situation, you may lose parts or whole of the file(s) involved in that FS operation or even the entire file system.
Some FS like NTFS uses a journal to record every FS operation before they are carried out, which basically eliminates file system integrity problems due to unsafe unplug or power loss.
However, most flash memory uses FAT which does not have a journal thus very susceptible to file system integrity problems. So it's always a good idea to remove a disk safely.