Had the same issue.
Using Windows 7.
Windows Explorer did not recognize the drive.
I went on KingWin web site for a phone number to tech support.
The tech (very patient, competent, etc.) talked me through the procedure in a couple minutes.
Basically, the drive needed to be formatted (even though it was recognized in the device manager as a WD 640 AAKS drive.)
As I recall.....
Click Start button
right click Computer
Click Manage
Left side of screen under Storage, click Disk Management
The hard drive in the EZ Dock 2535 should now show up in the main screen as disk 1, 2, or 3 depending how many drives you have.
It will also have a black bar above it.
My main internal hard drive (C:\) had a blue bar above it and was labeled as disk 0.
Now place the cursor in the box with the black bar above it (i.e. disk 1 or 2, etc.). its the box containing the hard drive in your EZ Dock.
Right click and select "Add simple drive"
As I recall, I just clicked "Next" on all the boxes that showed up after that (size of drive, drive label, format type, etc.) until clicking "Finish".
This is all from memory so I hope it helps..