Hard drive suddenly appears unformatted--possible to recover?

I have an external hard drive that suddenly appears as unformatted. It’s an independently powered USB enclosure. Windows still recognizes it. It shows up as

WD My Book 1110 USB Device [Hard drive] (1999.69 GB)

When I try to access it I get a message that I have to format it before I can use it. In other messages it tells me it failed a cyclic redundancy check.

I have tried to run chkdsk and it tells me the file system is type RAW, which is not compatible with chkdsk.

I was using it for backups and I think it was close to being full. I do not know what event may have caused it to appear unformatted. My suspicion is that something corrupted the master boot record and the actual data could still be intact, but I have no experience in disk repair and recovery.

Any suggestions?

I may come back to this, but at the moment just don’t use the disk in any way, writing, testing, formatting or anything. Disconnect the drive until you have a plan of action.
It happened to me before, but a long time ago, and it recovered.

Here’s a good guide to TestDisk

Litten — Drive becomes RAW.
It’s a long time since I used Windows tools, it might be best to use a Linux Live CD, of the Knoppix type meant for repair, to boot into and investigate the disk from there. [ A different operating system can usually see files invisible to the damaged operating system. ] And perhaps use those tools to repair.

I’ve used PhotoRec ( part of TestDisk ) and it has recovered files ( if you have another disk to transfer them to ), but it’s not a pleasure. Recuva is supposed to be good for this on Windows systems.
Still, it is very likely your files are OK. Just plan out the recovery.

It is possible that the master boot record became damaged, google: master boot record repair with the correct version of windows or whatever you are using.

I had this happen in a older version of windows (XP?) and is was as simply of getting a dos prompt off of a CD boot and typing something like chkdsk /mbr/repair <enter> (or something that easy) and I think it took seconds and I was back and running.

Are you trying to boot off this external drive? If not, why do you suspect a corrupted master boot record?

It’s possible that the problem is with the enclosure, not with the drive itself. You could try putting the drive in a different enclosure (or just reseating all the connections in its current enclosure).

I think the OP has confused the partition table with the MBR - a corrupt partition table is a more likely cause of the symptoms. However, it could just be a corrupt filesystem - the Windows NTFS driver very commonly has a panic at a file system issue that could very well be fixable - the Linux NTFS driver is much more tolerant of errors because it has been reverse-engineered and does more guessing along the way. So try Knoppix or something similar, try to get the data off, and then reformat the disk.

It’s quite likely the controller has died. You can often replace it.

If this is the case, recovery tools like Testdisk will not help. It won’t hurt to try, though.

Thanks for the responses. Yes, likely I am confusing MBR vs. partition table; this is not a bootable drive.

It is a factory-sealed unit; I can’t just pop it out of the enclosure.

Is there a seam you can pry open with a flat screwdriver? They’re usually just screwed together with tiny screws (maybe under a sticker?) or glued together weakly.

Here’s some crazy-sounding advice I got from an IT guy with a master’s degree and certification in both hardware and software, which actually worked for me.

Put it in the freezer. I’m not sure why it works-- it probably has something to do with shrinking the components, but anyway, when you have something to transfer the data to, try again, and then immediately copy all the data you need; after that, the drive is probably toast.

I swear to the deity, I did this with a dying harddrive, and it worked. I booted from a second drive, and tried to view the data on the bad drive, but it wouldn’t recognize it, which at first made me think it was a problem with the motherboard connection, or something. Anyway, after trying all kinds of things to view the drive, and thinking it was hopeless, I froze it. After about 10 hours, I was able to view it when booting from another drive (the drive itself should have been bootable, but I wasn’t messing with that). Anyway, I transferred all the data I needed, then tossed it.

Is this like a WD Elements or something like that? Because a lot of those external drives (if not all), you can actually just pry them open and pop them out of the enclosure. It’ll void your warranty (if that matters), but you can get to the actual drive unit and then pop it into an external enclosure. I’ve saved a couple hard drives that way.

ETA: Oh, duh, you say it’s a WD MyBook. Yeah, you can pry that open and you’ll find a regular ol’ hard drive in there connected to a circuit board which goes to the power supply and usb interface. You can just detach it like a normal hard drive and even pop it into an internal hard drive bay, if you want. (This will work if it’s your SATA bridge card that’s failed, which is what has happened to me a couple times.)

Not always - some external USB drives have native USB on the drive logic board. The cynical view would be that people were buying these and “shucking” them to get the bare drives inside, since the USB versions often sold for less than a bare drive. However, it is more likely that the drive manufacturers just did this because it saved space (no external converter board) and cost.

In any event, since the drive identifies properly, it is likely that the whole data path from the computer -> USB cable -> drive and back is working. A CRC error would tend to indicate a media problem.

My first advice is to not do anything to the drive (like trying to fix it, or putting it in the freezer - which was a hack to deal with a problem on one specific type of hard drive).

If you can find someone knowledgeable about data recovery locally, have them look at it. Of course, just because someone says they’re an expert doesn’t mean they are.

If I were dealing with this for you, I would make an image file of the entire hard disk, then run various recovery tools on the image. This preserves the original drive for another attempt, in case the first recovery doesn’t go well.

I’d also point out that any storage method can fail, regardless of it being a simple external drive, RAID, or cloud storage (yes, cloud providers sometimes exit the business). If it is important enough to keep, it is important enough to keep multiple copies of. A system that works well for many people is the original on the computer’s internal hard drive, a backup on one or more portable drives (which are not connected unless there’s a need to add or recover files from the drive) and a third copy on a cloud backup service. There are a number of cloud services that are flat-rate (or functionally flat-rate, as their minimum storage can be more than you need). You can encrypt the files before sending them to the cloud service if you’re concerned about privacy - just don’t forget the password!

I have done this and it worked for me too. I should say that it was with equipment that would be considered antique these days.

Seal the drive in a freezer bag to keep moisture out.

I have a Win machine that apparently doesn’t recognize the “disk change” signal for the floppy drive (yes, I use floppies sometimes). So if I remove a disk, put it in another machine, add or subtract a file name where the directory is altered, then put it back in the original machine, I get the message “disk not formatted.” That sounds like what is happening in your situation.

If I put the disk in machine #2, it reads perfectly. In your case, I’d try reading it in other machines, or with a different USB enclosure, or as a bare drive if you can. Don’t write anything on it at all! If it reads one of those ways, it’s not a damaged drive, just a misinterpretation.

Just wanted to bump this thread as I have the exact same problem. Mine isn’t bootable either, but is in an enclosure I can take it out of. I had tried the freezing thing, but that didn’t help (well, actually it may have - not sure whether I got the “unformatted” message before trying that or just after - at first the PC didn’t recognize it at all). I’ll try plugging it into my laptop when I get home, and some of the other suggestions above. Even though I’m not the OP, thanks for the suggestions.

I had a similar problem years ago. I was able to recover it with a tool. I’ve got two partition recovery tools kept in my folder of useful installers. I can’t remember which one I used, but here are the links to download.

If all else fails, there are services that can recover data from a dead hard drive. You will pay through the nose (at least a grand), but they can do amazing things.

And you will learn a most valuable lesson. Always have a backup. Or two.

The OP said that this drive was being used for backups. So presumably whatever is on it is duplicated elsewhere. Is that true, CookingWithGas, or are there files on this drive that don’t exist elsewhere?

Don’t try the freezer trick! That’s for when the drive appears to have died, which is not the case here. You’re getting a logical error, not a physical one.

A partition recovery tool should resolve the issue in seconds.