external hard drive not recognized

I have two Western Digital 300GB, USB3, external drives. Suddenly both are not recognized by Windows.
1) Neither appear as a drive in File Explorer

2) Device Manager reports that the "device is working properly", and the drivers are up to date. There is a message in Events that says "device not migrated"

3) Disk Manager shows the drive with the following information: no Drive Letter, Unknown, and not initialized. Right clicking shows the menu options however Initialize is greyed out and not available, clicking the Offline button results in message that says "device not ready"

I tried a third party program (AOMEI partition assistant standard) but it also could not initialize either of the drives.

Any suggestions would be greatly appreciated, thanks

If a device shows the error “Device is not migrated”, it can be caused by damaged or non compatible drivers.

1. Launch device manager and use the Uninstall button for external storage drives.

2. If a dialog box asks to delete the drivers, check the checkbox for deleting the driver files from Windows driver store.

3. Reboot Windows after uninstalling the driver and then let device manager search for new device drivers.

thanks FreeBooter
I tried the method that you suggested, but unfortunately it did not work, but the symptoms are now slightly different.

When I go to Disk Management the information for the disk is: Unknown, Not Initialized.

However this time the initialize button is not greyed out, but when I click on it the message is "device is not ready", I get the same error message when I click the Offline button.

Can you please post screenshot of the Disk Management console.

Fix or rebuild MBR

1. Download and launch EaseUS free partition software.
2. Select the external hard drive, right-click and select "Rebuild MBR", and then choose the proper Operating System version.
3. Apply the operation to add a pending operation of rebuilding MBR.


Check and repair bad sectors and disk error

1. Download and launch EaseUS free partition software, right-click the hard drive and click "Check partition".
2. Choose the way that you want to use to check and repair bad sectors: "Check Partition Properties", "Call Windows Chkdsk" or "Surface Test" and Click "OK" to continue.
3. Let the software automatically check and repair bad sectors. And finally, click "OK" to finish the process.

I downloaded EaseUs partition software, when I run the software it does not show the external hard drive in the list of connected drives, it only shows my main internal drive. Windows disk manager continues to show the external drive however with the same unresponsiveness.

This is a Windows version of the Data LifeGuard Diagnostics. It will test WD internal and external drives. Please do a EXTENDED TEST on the external drive - performs a Full Media Scan to detect bad sectors. Test may take several hours to complete depending on the size of the drive. Please post the result of the EXTENDED TEST.

hello FreeBooter
I did the extended test here are the results:
capacity 0.00 GB
SMART status - not available
test result PASS

by the way FreeBooter the test took 1 second, I assume because the capacity is detected as 0 GB, I don't know

Looks like Master Boot Record (MBR) is damage try rebuilding MBR with MiniTool Partition Wizard.