this is going to sound like an obvious question, but have you tried using a different USB cable??
i'm asking because it sounds like the signal from the drive is either being corrupted somehow or just flat out not responding properly. hopefully, its something as simple as the cable because if it isn't, then its likely the HD itself.
i'm going to assume that its under warranty; so if it is the HD, it should be a simple matter of contacting WD for support.
See the struggle of the faithless lot as they negate their time
How low to sink to the depths of their frame of mind