I'm not sure what happened. I was using it to back up an older drive with what's on my WD. The batter died on my Macbook Pro causing the back up to end prematurely. When I restarted the computer, on my older drive would come up. The WD My Passport is missing from the Finder. I can see it in Disk Utility but that's it. No option to repair. I've been doing some research and WD has been having this same issue for some time. I have nearly 1TB of data on this drive that extremely critical and I don't know what to do. Can someone help?
I had a similar problem with WD My Passport not mounting, which I was using as a time machine backup. Eventually found a (temporary) solution to it not mounting by opening Activity Monitor (while the drive was connected) and selecting process "fsck_hfs" and then "quit process". The drive should then mount on the desktop and enable you to access the drive/contents. I'm not sure how the drive can be permanently repaired but in my case I reformatted it - and now it's behaving.