I am hoping this questions hasn't been asked and answered a dozen times, but I have looked.

I have a WD10000H1U-00 1TB external drive formatted with NTFS. It has worked perfectly for however long I have had it. Starting last night it began to act strangely. While the drive and all of its contents are available after I reboot, at some point they begin to disappear along with the directories. Finally Windows shows an empty drive, however the drive properties still show what I should be the correct used and free space. Along with that the the event log shows {Delayed Write Failed} messages. The strange thing is that it I reboot the machine the files return in all their glory.

When the drive is functioning Chkdsk returns no errors, when the files disappear Chkdsk cannot access the drive,

From what I can gather I mostly likely have a firmware, controller, or power supply problem, but I can't be sure. Are there any further tests I can run to troubleshoot this further?

The good news is that all of the data is backed up. Actually, mostly this is a backup drive to begin with but all files is my system are stored on at least two pieces of hardware and usually more. (I am a good boy!)

Thanks for all your help.

Well done for spotting this. Unfortunately that is a very general Windows error message, basically saying that a write which had been cached on the host (often a filesystem metadata update) could not be successfully written to the storage at a later time - but at the level of that message, it doesn't know (or care) exactly why the write failed. The consequence will be exactly as you describe - parts of the filesystem will become inaccessible to Windows, as these filesystem updates fail. Are there any other odd event log messages shortly before those ones?


That is expected for intermittent errors, until the next filesystem metadata update failure occurs.


Actually the list of suspects is longer (e.g. could be internal drive problems) - unfortunately any problem which causes an I/O failure on a metadata update, can cause the results which you describe. A drive firmware problem is highly unlikely, as this drive has been working OK for a while.


As the data on the drive isn't needed and we don't have to worry about the possibility of "diagnosing the drive to death", I suggest gathering the full SMART data from the drive, including raw attribute values (smartctl (specifically smartctl -x) from smartmontools is one suitable utility, but there are many others), so that this data can be reviewed. The advantage of running smartctl -x is that the drive's [standard] internal error log is also collected, and that can give better insight about a potential problem than just the SMART data, in some cases.

After collecting that SMART data (and ideally the internal error log) from the drive, you could download & run the full WD DLG (Data LifeGuard) test and see what result you get. However if the problem with the drive is specific to writes, then it is possible that this test will pass (as always, a test which passes does not prove that everything is OK).

Hope that gives you some ideas.

Wow, thanks for the quick and thorough reply.

My hope was that the problem was not the drive itself, but in the external pieces. From what you wrote I am not sure if you are saying that it probably IS the drive itself. If that's the case then I figure my best best bet is to ditch it and replace it and not worry to hard about diagnosing it.

If I am incorrect in this then please let me know and I will work a little harder on determining the disease.

You're welcome


I'm saying that the problem might be the drive itself, but that the cause cannot be determined just from the information available so far, as that Windows error message can have many possible causes - it's basically an I/O error message, but is telling you about a symptom and not its cause. That's why I explained about gathering the SMART data (and internal error log) as one way of trying to better understand what type of problem there might be, which is one step closer to trying to understand the true cause.

Depending on what time & money you want to spend, what other equipment you have available, and how often this behaviour happens (i.e. how intermittent it is) you could move that drive into a different enclosure / PSU etc. and see if the problems move with the drive. If not, then the problem might be related to some other component. There are various different troubleshooting approaches you could use, each with their own pros & cons. Or you could just buy a new drive, give it a really good, long test to get some confidence that you don't have a "lemon", and use that for your backups instead. Your choice Hope that helped clarify what I was trying to say.

P.S. If you do decide to ditch your original drive, then make sure to fully erase it first, after your backups are definitely confirmed as readable elsewhere. You might be able to sell the drive (or its PCB) on Ebay etc. for spares or repair.

Hey, did you get to the root of this issue by any chance?

I have EXACTLY the same issue at the moment.
Everything is on the drive when I boot up and then it gradually disappears until the next boot, sometimes a few minutes, sometimes I get an hour or two out of it until everything starts disappearing. This is also my backup drive a (WD 400GB), and I lost my main storage drive last week in a Windows 10 related incident so all my pics, movies music are on it.

My SSD a week before too!!

AHHH..
P.S. the drive is fairly old.. maybe 7 years (4 working), but works fine until the Houdini act..

This is funny. I returned to this forum to post about a similar issue and had forgotten that I had ever posted this topic.

Honestly, I can't remember what I found out about that old hard drive. I am sure that by now I replaced it. If you are still waiting then I will say that Vulcan's replies were perfect for analyzing drive issues, but I would suggest that given the falling prices for hard drives the better course is to replace any drive that it giving you issues. These symptoms are usually the canaries in the coalmine.

Good luck!