I also have another Mybook and it's 1T, it is showing up as disk 2, so you can ignore that one, my 750 is the one I'm having issues with.
I have removed the drive from the casing and put into a SATA HDD USB docking station to see if something happened to the wiring of the WD MY BOOK. The drive is still spinning and there are no unusual clicking sounds.
I have tried the program GetDataBack and it could find the drive, but was getting errors reading it, though I am not really sure if I am using the program right. I have also tried Un-Delete Files, HandyRecovery, and SpinRite, and none of them could even pick up the drive.
I have alot of data on that drive that is very important to me and I would really like to get it back. My 1T is completely empty so I could transfer all of my files to that one. Thank you for taking the time to read this and any suggestions you may have for me would be greatly appreciated.