I can't find and access my external HDD?

Hello,

The external hard drive may have encountered a corruption the reason why you can't access it on your computer. The error indicates that the hard drive is about to fail or has already failed. The S.M.A.R.T. system is a utility that monitors the health of the hard drive and reports any potential problems. For us to verify if we can still retrieve the files on your hard drive, kindly follow the methods below:

Method 1: Run the hardware troubleshooter and check if it helps.

1. Press Windows and X key together and select Control Panel.
2. Click on Troubleshooting.
3. Click on View all option on the left side of the Windows.
4. Click on Hardware and Devices option.
5. Click on Next and follow the onscreen instructions to troubleshoot the issue.

Method 2: Try connecting the external hard drive to a different USB port and check.

Method 3: Check the disk management and see if the hard drive is detected. If it is detected, change the drive letter and go back to the Windows Explorer and check if you can open it.

1. Open Disk Manager by pressing Windows key + R, type in diskmgmt.msc in the run prompt, and press Enter to open Disk Management that will list all the disks that are connected to the computer.
2. Check if you can see the USB drive if it is listed.
3. Right-click the drive, and click Change.
4. Click Assign the following drive letter, click the letter that you want to use, and then click OK.

Kindly get back to us with the results.

Hello and thanks for getting back to me.

Methods 1 and 2 yield no results and for method 3, I don't think it's listed.

I have disk 0 partition 1 and disk 0 partition 4, Data (D:) and OS (C:).  

When I eject the external HDD it changes nothing.  My PC recognises that it's plugged in and what it is, but won't let me access it.

Hope that's enough information

It's an Hitachi HTS721010 A9E630 Travelstar 7 K1000 1000 GB HARDDRIVE 2.5 Serial ATA, and the external HDD is the same.  

My PC understands that it's there, and let's me know that I can safely eject it etc but not that I can use it.  The only two options in "This PC - Devices and Drives" (when plugged into the laptop) are OS (C:) and Data (D:).  

In Disk Management it is recognised as "Disk 1 / Basic / 931.51 GB / Online | Unallocated".  When I right click it, it offers me the option to convert to "Dynamic Disk" or "GPT Disk".

We appreciate your reply. For further investigation, we'd like to know the make and model of your hard drive and you mentioned that it is not listed at the Disk Management, for clarification isn't it recognized by Disk Management?

On the other hand, most HDD manufacturers offer their own recovery services or have some recovery partners the main reason why we're asking for the make and model. We also suggest that you try changing the USB cable as well as connecting the drive to another port.

Kindly get back to us for further assistance.