WD My Passport 1TB USB3.0 WDBBEP0010BBK-01 - Problem with Windows 8.1

WD External Drives WD Portable Drives
2

first make sure the USB drivers and controlers are up to date. Sometimes the USB data gets jumbled up. I sued this on my sister’s windows 7 

http://www.techspot.com/community/topics/usb-drive-or-flash-problems-how-to-cleanup-and-remove-old-usb-storage-drivers.145884/

Joe