HDD was seen by my PC, but after 3rd party format it is not visible

I have a 500GB Iomega External USB HDD that I had been unable to format thru disk manager for other wise. After reading various recommendations I used the "Hard Disk Low Level Format Tool" program. When the format was finally complete a window popped up saying I need to make it a GPT disc or Master Boot. I want it for back-ups and disc imaging. In Computer Management it shows as Unallocated, but in Explorer it does not show up. Did I do something wrong or is there more to be done?

A low level format writes zeros to all sectors.

After successful low level format, you have to do a regular format.

So go ahead and format it as an MBR disk.( You got the right message. Just select MBR and go ahead to format it.)

I'd love to do that, BUT...
The only shows as "Disk 2" in Disk Management, on the lower half of the right side. It does not appear in the upper half where my C: drive is.
It is also visible under Device Manager
I thought maybe I could format it from Command Prompt, but with no drive name, that won't work.
So what do I do now?

Hi,

Shut down your computer.

Please plug out all external USB drives/pen drives.

Reboot your computer and plug-in only the external drive which you have low level formatted.

View your disks in Disk Management

If you get an Initialise Disk screen as in the following screenshot, choose MBR and click on OK.

That will write the MBR to the first sector and that disk which was " Unknown, Not Initialised, unallocated" will turn into "Basic, Online and Unallocated". Right click on where it says Unallocated and create a Simple volume and format it.



If you do not get an initialise screen, rightclick on the Disk icon with a downward red arrow, click on Initialise Disk and follow what is stated above.

Usually I am able to figure this stuff out for myself, but this one has me frustrated.
I followed the previous instructions and I now have a Drive E:, Simple layout, Basic type, but Windows would not format it, and despite that fact that it is "Healthy (Primary Partition)"; it's file system is listed as raw.

Which program did you use to low level format the drive?(If need be I may ask you to LLF with a program of my choice and start afresh.)

Now try formatting it with HP USB Disk Storage Format Tool 2.2.3 HP USB Disk Storage Format Tool Free Download

Right click on the .exe file and run it as administrator. ( Ensure that you select the correct drive)

Report the results.

Well, I wish I could say it worked. Even though it's Status is Healthy it refuses to be formatted. Could I totally wipe it clean and start again? In the beginning of all this the drive showed up as blank, so I thought the "HDD Low Level Format Tool" would do the trick.

Pooky1959 said:

Well, I wish I could say it worked. Even though it's Status is Healthy it refuses to be formatted. Could I totally wipe it clean and start again? In the beginning of all this the drive showed up as blank, so I thought the "HDD Low Level Format Tool" would do the trick.

Please answer the questions to the point.

1. Did you run the HP formatting Tool as an administrator? yes/no

2. What exactly is the error message you get if it is refusing to format? ( Just saying it refuses to format does not give us any clue). Please take a screenshot of the error message and post, if you cannot note it down and post it verbatim.

3. Take a screenshot of how your Iomega External HDD looks in Windows Disk Management. ( Not to confuse, remove all other external HDDs/pen drives)

Disk Management - Post a Screen Capture Image

1. Yes, to running it as admin
2. The message said "Failed to format the device"