How to Copy from 1 4 TB MY Book to another

I have successfully backed up data on to one of my WD 4 TB External drives. I want to copy from that drive to another drive. When I run the unlock function on my original drive it opens the My Book partition and assigns it as my H: drive. When I connect my 2nd drive and run the unlock function I do not see the partition come up. I suspect the unlocked partition always defaults to H:. How can I change this default? Or is there a better way to do this?

Thanks for any help you can give me.

Hi there,

And what happens if you only put the second drive in does the system unlock it? Try to change the letter of the second drive to see if this way it shows up. Hope this helps

Either drive that is inserted first defaults to the H: drive. I cannot find where I can override the setting of H:

Hi there,

Here is a link that might help you:

http://windows.microsoft.com/en-us/windows/change-add-remove-drive-letter#1TC=windows-7