As I stated before, if Windows Disk Management cannot see the PS2 disk, then no PC program will see it including WinHiip. WinHiip does not talk directly to the PS2 drive. It will call Windows raw disk APIs.
Again, it's Windows Disk Management. Not windows explorer, etc. Here's a sample picture
So if it's not listed as a disk there, then WinHiip is not going to work. It should look something like disk 3 in this picture:
I found one IDE drive that did not work with the USB cable in my house. It's an old 8GB drive from the original xbox. It is an EIDE (Enhanced IDE drive). The other drives are ATA 133. I wonder if this might have something to do with it?
What type of drive are you trying to use? What's the manufacturer/model of it? Does it say ATA 66 or 133 or EIDE?