My passport 1TB and 4TB external drives will not open or remain available even though they appear on the desktop and in my finder on my Mac. I am using OS High Sierra. Also, they don’t eject when eject is selected, I have tried to “Force Quit” and it gives me a message that it cannot force quit. I tried the log out and log in, no joy. I have to disconnect the drive manually and reconnect both manually then it will open however, after awhile it will not open again.
Try removing the WD Discovery software, did the trick for me. Make sure to remove every single trace of WD software, it interferes with MacOS’ ability to wake/sleep hard drives.
