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Windows 7: Unable to access or format external hard drives

31 Jan 2014   #1

windows 7 ultimate x64
Unable to access or format external hard drives

I have 2 ADATA 500 GB external hard drives. I plugged them into the USB port and the computer recognized them by name and installed the driver files. It assigned both of them a drive letter but then gave me a message saying that they needed to be formatted. I clicked ok since they are brand new drives and do not have any data on them, but the format failed to complete on both drives. I took both drives to another PC running Windows Vista and they were recognized and accessible. I even transferred a few files to them for testing purposes; however, when I plugged them back into my Alienware laptop running Windows 7 Ultimate x64, then I got the same error. If I go to the disk manager, then I can see the drives by their drive letter and they are listed as healthy with a primary partition but the file format shows as RAW. I tried to use the device manager and uninstall the USB Mass Storage Device drivers for each drive and then I unplugged them and plugged them in again and I would get a device driver installation message that identifies the drives by name and tells me that the device drivers were installed correctly and that my devices are ready for use but then a few minutes later I will get a message telling me to format the drives. Please help. I've run out of things to try. I can still access my iPhone via USB and my USB wireless mouse still works so I know my USB ports are good.

My System SpecsSystem Spec
31 Jan 2014   #2

Windows 7 ultimate 64-bit

Try this link and see it helps ya any:

Windows Unable to Format External Hard Drive
My System SpecsSystem Spec
02 Feb 2014   #3

Windows 7 Home Premium 32 bit

Welcome to SevenForums, Professor.

Vista can read the two AData drives but your Windows 7 PC only shows them RAW and format fails. Strange.

You said some other USB devices like iphone look OK on your PC.

But what I would like to know is what happens when you plug in any other USB HDD/pen drive. Do those read and write OK?

EDIT: It is hard for me to believe that RAW drives had a drive letter assigned. Can you please post a screenshot of Windows 7 Disk Management with the two AData HDDs plugged-in?
My System SpecsSystem Spec
03 Feb 2014   #4

windows 7 ultimate x64

matts6887: I tried the link that you provided and got a couple different things to try such as; downloading and using Partition Wizard and using Windows DiskPart command. I opted for the latter because its free and already a part of my Windows tool kit.

jumanji: Yes sir, I have several external hard drives That I keep for backup and other stuff and they all still work with my Windows 7 laptop. The only problem that I'm having is with these ADATA drives.

Here is the real kick in the teeth: I took this screenshot right now. I have already ran diskpart on the external hard drive which allowed me to format it with a file system of NTFS and a label called "red". The next two screenshots are from my Vista laptop with the red drive. One is from the disk management and the other is a screenshot showing where I had copied some pictures to the drive. I still cannot open this drive with my Windows 7 laptop.

Attached Thumbnails
-disk-management-screenshot.jpg   -disk-management-snip-vista.jpg   -my-adata-drive.jpg  
My System SpecsSystem Spec
03 Feb 2014   #5

Windows 7 Home Premium 32 bit

That beats me anyway.

Now just plug-in only the two AData drives to your Windows 7 PC ( remove all other USB storage drives) and post the Windows Disk Management Screenshot. (Please go to the toolbar, click on Show/Hide Console Tree, Show/hide Action Panel to hide those so that we can get a full screen view.)

Once you had taken this screenshot to post, do the following.

Of course now I am going to shoot in the dark , but based solely on some user reports.

Download AOMEI Partition Assistant Standard directly from the author's website Free Partition Manager - AOMEI Partition Assistant Standard - that will take you to cnet - install and run with both the drives plugged in.

"Though the app will reformat and / or partition your drive, the first step is to select the external drive in question and then select Properties. It is our mutual experience that this is often enough to get the drive recognized by Windows.

Another approach is to use the following Fix It troubleshooter, here: .

Try these approaches and let me know if this fixes the issue for you."

Yep, I have merely copied and pasted from one of the latest posts in Microsoft Community.

Let us know what happens.
My System SpecsSystem Spec
03 Feb 2014   #6

x64 (6.3.9600) Win8.1 Pro & soon dual boot x64 (6.1.7601) Win7_SP1 HomePrem

Follow jumanji's suggestions first, then
if the issue is still not not resolved...

I'm referring to the two new drives, so no backup is required - right?
I'd like you to use diskpart and put the drive in an uninitialized state. Then disconnect the drive gracefully

As a matter of fact, disconnect all USB devices except those you need (mouse, keyboard) - if you get by without those (if you have them) - disconnect those devices al well.

Remove the disc from the OD.

There are a few things I see in the Win7 Disk Management screenshot.
I'm not familiar with Toshiba disk partitioning, but I'll echo the disk/parts as I read them

Disk 0:
  • part 1 -> OEM [39 MB]
  • part 2 -> RECOVERY (System, Active, Primary) [14.11 GB]
  • Part 3 -> OS (Boot, Page, Crash, Primary) [462.789 GB]
Disk 1:
  • part 1 -> Unallocated [101 MB] --- looks like a system part
  • part 2 -> Toshiba Ext (Active, Primary)
Disk 2:
  • part 1 -> RAW [465.76 GB]
Please fill in your system specs so members can easily reference your system: System Specs (see How to - System Specs).
I'd like to see a Device Manager (DevMgr) screen shot(s) showing View->Show hidden devices, but
before opening DevMgr I want you to add an environment variable to your user profile
with a value of
Once the variable is set, Open DevMgr, View->Show hidden devices and expand the following:
  • Disk drives
  • Storage volume shadow copies
  • Storage Volumes
  • Universal Serial Bus controllers
post the information shown in the screenshot(s).

Follow this tutorial and post a new Disk Management screenshot: Disk Management - Post a Screen Capture Image
At this stage I expect to only see Disk 0 - no other drives connected.

My System SpecsSystem Spec
04 Feb 2014   #7

windows 7 ultimate x64

Jumanji: I have provided the screenshot that you requested sir. I also followed your instructions and downloaded AOMEI and provided screenshots showing where I accessed both drives. The drive labled red is the only drive that I used diskpart on and actually performed a format to NTFS. I haven't done anything to the second drive. I thought that I should concentrate on getting at least one drive going first and then trying to get the second one once I succeeded with the first.

Slartybart: I don't know how to add an environment variable to my user profile, but I did go ahead and post a screenshot of my device manager. I couldn't get the entire list in one screenshot but I did cover the expanded areas that you requested.

Attached Thumbnails
-disk-management-screenshot-2.jpg   -aomei-screenshot.jpg   -reds-properties.jpg   -drive-2s-properties.jpg   -device-manager.jpg  

My System SpecsSystem Spec
04 Feb 2014   #8

Windows 7 Home Premium 32 bit

OK, the drive you formatted with diskpart labelled red does show up in AOMEI PA as having the file system NTFS and also shows the used space ( the files you copied) but still without a drive letter. Windows however does not recognise any and shows as RAW.

The drive you left in virgin state, shows as unformatted but with a drive letter E in AOMEI PA and shows as drive E and RAW in Windows Disk Management.

Let us see what Slartybart has to say about it. My analytical skills have stopped dead .

I would think our strategy now should be to deal with just one drive - the one you still left in virgin state - and make it recognisable with Windows 7, by whatever means.

If Slartybart's idea is to see the non-present devices - yes, non-present devices that had already been assigned a drive letter but continue to be present in Windows list without releasing the drive letters - that may confuse the Windows, I do have an alternate plan to do the drive cleanup but as I said I shall wait for Slartybart.

( In the meanwhile you can prepare yourself to do that Nagging on non-existant drive. Even if you go ahead with it without waiting for Slartybart, there is no harm since a periodical drive cleanup is a recommended practice especially when one keeps on plugging-in and out various USB drives but I want you to wait so that we do not pull in different directions.)

EDIT: You haven't said anything about trying Did you try it?
My System SpecsSystem Spec
04 Feb 2014   #9

x64 (6.3.9600) Win8.1 Pro & soon dual boot x64 (6.1.7601) Win7_SP1 HomePrem

qcddoc2012 & jumanji

I'll wait until this is answered:
EDIT: You haven't said anything about trying Did you try it?

Then I'll work back off of post 6.
It's easy to add an enviroment varialbe, I'll walk you thru that.
Then clean one of the troublesome drives

I want to get Disk Management showing only the C: drive (Disk 0) and then clean up ghosts n DevMgr
Then connect the uninitialized drive to Win7
Use Disk Manager to inialize to MBR and format NTFS
(might have to initialize in Diskpart, I forget)

and go from there.

That's what I had in mind... but first about the MS Fixit (Mats) - did you run it and did it have any affect?

My System SpecsSystem Spec
04 Feb 2014   #10

windows 7 ultimate x64

Thank you gentlemen I appreciate all of your help. I did try the Microsoft fixit link. However, when I posted I had used my limit of attaching snapshot posts so I left it out. I went to the link and ran the fixit application but it failed to run because the error message said the troubleshooter was invalid or that it might have expired. I attached that snapshot to this post.

Attached Thumbnails
My System SpecsSystem Spec

 Unable to access or format external hard drives

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