WD External Hard drive not recognized in my computer

I don’t know if you have solved your problem yet or not.  (I am still wading through the whole thread.)  I had a similar problem with my WD 500 GB portable drive too.  I found a great program that has allowed me to restore my data.  It is called Zero Assumption Recovery.  It costs about US$50 to purchase online and you have to have another driver to save the recovered data to, but it was very easy to use.  I used the “recover current data” and it found every single file… as far as I can tell.  (I had over 400GB of data.)  This was the best $50 I ever spent.  The scan does take a very long time (almost 20 hours) but part of that might have been the processor on my labtop!!  :-)  I hope this helps!!  Good Luck!!