All files disappeared!

WD External Drives External Drives for Mac
3

Sorry, maybe I was not clear.

  1. Files are on the Book.
  2. I connect the Book to my QNAP Nas.
  3. I test transfer of a file from Book to Nas.
  4. File is transferred correctly.
  5. Back to my Book, it’s empty. All files gone.
  6. Connect Book to Mac for a double check. Confirmed, Book is empty.

I suspect some kind of reciprocal sync between Book and Nas.

The issue is not the Mac.

My question is: how can I recover the lost files from the Book?

Thanks.