What you can do is
Check The State of WD External Hard Disk in Disk Management
Connect the WD external hard drive to your computer via the USB cable. Follow steps here to check the state of your WD external hard drive in Disk Management:
Step 1. Press Windows + R keys, type diskmgmt.msc in the Run box, and click “OK”.
Step 2. In Disk Management, locate and check the state of your WD external hard drive.
Add New Drive Letter to Make WD Passport External Hard Drive Showing Up
Applies to: Fix WD passport external hard drive not showing up due to the drive letter confliction.
If your WD displays as “New Volume” with no drive letter in Disk Management, it won’t show up in File Explorer. Don’t worry.
You can change or add a new drive letter so to make WD passport detectable and accessible again in Windows PC:
Step 1. Press Win + R keys, type diskmgmt.msc in the Run dialog, click “OK” to open Disk Management.
Step 2. Right-click on WD drive which fails to show up and choose “Change Drive Letter and Paths…”.
Step 3. Click “Add”, set a new drive letter to assign to the WD external drive, and click “OK”.
If the WD drive has already been assigned with a letter, click “Change” to choose another letter for it. After this, restart your PC and check if you can visit the WD external hard drive in Windows File Explorer.
When the WD Passport drive is not working, it might be caused by the outdated device drivers. So the best way is to update its driver via the following three paths:
#1. Download and Install WD Device Driver:
Step 1. Connect the problematic WD external hard drive to your PC.
Step 2. Right-click on the Windows icon and select “Device Manager”.
Step 3. Find and expand Disk Drivers, Portable Devices, Universal Serial USB Controllers, or Other devices.
See if the WD external hard drive is shown as an “Unknown” device.
Step 4. Right-click on Unknown or not working WD external hard drive, select “Properties”.
Step 5. Go to the Details tab, set Property to “Hardware Ids”.
Step 6. Right-click the top Value and click “Copy”.
Step 7. Paste it into a browser and search for the correct device driver.
Step 8. Find and download the correct WD device driver and install it on your PC.
After this, restart your computer. And everything shall work fine with your WD My Passport Ultra drive.
#2. Update WD Device Driver from Device Manager:
Step 1. Right-click on the Windows icon and select “Device Manager”.
Step 2. Expand Device Manager and right-click the WD My Passport Ultra drive.
Step 3. Select “Update driver”.
Step 4. Select “Search automatically for updated driver software”, wait for the process to complete.
I hope this will help you out.