WD My Book

Try OPTION - drag to trash. That usually overrides the warning you see.

The MyBook external enclosure is not a high-quality bit of kit. Mine gave me a huge amount of trouble—stalls, slowing the computer, making the computer run hotter. I removed the bare drive inside, reformatted it to get rid of WD's kludgy and proprietary partitioning scheme, and placed it in an OWC Mercury Elite Pro enclosure and it is still working fine today over a decade later.

As suggested by ku4hx, any issues with the MyBook are exacerbated if you installed WD's drive management software on your computer. It is unneeded, and even WD support techs have told Mac users not to install the apps.

I'm guessing a My Book is an external drive.

You can clear its contents by erasing the drive. reformatting it, in Disk Utility. Try First Aid.

If a WD app is causing a problem, 3rd party drive software is rarely needed, uninstall it by dragging it to the Trash. Or by using the app AppCleaner.

Or for a really stubborn drive, detach it from your Mac and try and determine if it's usable on a different Mac. If it can't be, it may have failed

Or you ca reformat it on a Windows machines and then go back to your Mac.

Or you can use a partitioning app, such as GPartEd to reformat it.

FWIW, I don't have the WD My Book, but have the WD My Book Pro. Regardless, it doesn't require any WD software that may have come with it in order to use it with your Mac. As such, and as @ku4hx has already suggested, you should completely remove any WD software from your iMac. Doing so, should remove any warnings about other programs using it.

Once that is done, the other excellent suggestions that were already provided to you, should be followed. In my experience, I've had never experienced a drive failure with WD devices ... but that doesn't mean that they don't happen.

Tesserax wrote:

I've had never experienced a drive failure with WD devices ... but that doesn't mean that they don't happen.

My MyBook never technically failed, it simple never worked up to very reasonable expectations. All of our external OWC enclosures have WD Black 3.5-inch drives and we even have one of the rather maligned WD "Green" drives that I pulled out of a MyBook Mac Edition and cleaned up 15 years ago that still works fine (although, in deference to its age, it's not seen "mission-critical" assignments in a long time). Their bare drives have been quite reliable in OWC enclosures. However, IMHO WD need an enclosure czar to clean house.

It's WD's proprietary formatting on external drives—even those sold as "Mac Editions"—and WD enclosures, including the MyBook and Passport, that were sources of my grief and others whose Macs I shepherd.

Thanks Allan. You bring up a lot of good points. Along with the My Book Pro, I have accumulated a number of My Passport devices. None of these have failed, but I do admit when WD starting implementing "locked" partitions on these, I was less than thrilled. Never used their included software, so I really can't address that.

I totally agree with OWC gear. I have been a customer of theirs for years. Never been disappointed. "Rebuilt" a number of older Macs, including this 2010 MBP, which I am writing this post with.

FWIW, I rely more on my Synology NAS for external storage and for Time Machine backups. I also like their "Active Backup for Business" app to handle both incremental & "bare metal" backing up of my Macs, & Windows/Linux PCs.