I have a WD MyBook for Mac and MacBook Pro (Big Sur).
When I try to unlock the MyBook by clicking on WD Unlocker > WD Drive Unlock > usually I can enter a password, but instead I get the error message below:
“You must run the WD Drive Unlock application from the WD Drive Unlock CD associated with the drive you want to unlock.”
How do I fix this so I can access it?
https://downloads.wdc.com/wdapp/WD_Security_Standalone_Installer_Mac_2_1_1_81.zip
Try to download the standard app from WDC website above. Install it and use it to unlock your drive. I noticed you are using Big Sur OSX. The app might or might not work on that OSX. But give it a try
Thanks it worked!
Hello, I have the same problem as DT12444. I have down loaded the standalone installer - no success.
The message “you must run the WD unlock application from the WD drive unlock CD associated with the drive you want to unlock” still appears.
This has happened after I started using macOS big sur 11.6.2.
My family life is on this drive. Can you help please.
Kind regards
You can’t install the standalone installer from online? In that case you might have to call WD if they have any other version of WD unlocker for you to try out.
Thanks for replying. Apple advised their BigSur OS does not recognise the WD external drive as is. They said to reformat with their tech support help. This would delete all files OR Downgrade macOS to Catalina if I want to retain files on the WD drive.
I attempted all WD suggestions with no success.
Cheers 
If downgrade the MacOS to be able to unlock the drive then you should try it. At least you able to back up your files to another drive then you can upgrade back to a newer OS. Or you can try if anyone else you know using an older Mac. Hope you able to get your important files back. Have you try to call WD Support help line?
