New 1 TB My Passport Ultra inaccessible after drive exits sleep mode

Brand new drive.  Works great as long as it is not allowed to go to sleep (the drive, not the computer). Once the drive goes to sleep (slowly blinking LED) any attempt to access the file-system on it will result in about 60 seconds of the LED showing activity (rapid blinking) followed by an I/O error reported by the OS.  The drive will not be accessible again until it is unplugged and plugged back in. I’ve tried the drive on a Windows 8.1 desktop and a Windows 7 laptop, and the behaviour is the same on both.  All diagnostic tests available in the “WD Drive Utilities” tool pass, including the complete drive test. The firmware update utility reports that the drive is already running the most current release. 

Hi, it is possible that the Passport is not getting enough energy to work correctly. Be sure to use the USB cable that came bundled, avoid USB extension cables or USB hubs. You can also run a DLG test. 

How to test a drive for problems using Data Lifeguard Diagnostics for Windows

I was using the cable that came with the drive.  Drive was plugged direclty into the USB port on each machine I tested it on. Tried it on 3 different computers, one was USB 3.0 and the other 2 USB 2.0.  I tested the drive with Data Lifeguard tools. I also deleted and recreated the partition, and reformattted it, and even tried reflashing the firmware.  It’s on it’s way back to Amazon tomorrow. Replacement on the way.  Looks like I just got a dud. 

New drive arrived today.  No issues returing from sleep mode on any of the three machines I tested on with the first unit. Appears the first unit was in fact, defective.