Just taken delivery of a brand new 27" iMac today. One of my four WD ext drives won’t mount - the one with my back-up on, of course.
Although the original SmartWare software appears on the desktop to launch, the drive doesn’t. It can be found in Disk Utility but is grayed-out. The info shows it is still clock-full of data (glory be) but no amount of First Aid will tease it out.
One hour with AppleCare wasn’t successful - any bright ideas? Please.