Im having the exact same problems as mentioned in this thread >>> http://community.wd.com/t5/WD-Portable-Drives/My-Passport-2TB-always-connects-disconnects-and-horrible-speed/td-p/692012
Did everything, WD diagnostics came out clean, low level format (found 0 bad sectors) it’s just a problem with the drive itself after the latest firmware update. Original firmware never had these issues! and wha’ts worse, WD won’t offer us a downgrade which is a simple fix!! WOW!
last WD driver I buy in my life!