Did you ever resolve this issue? I had a drive replaced, and I am trying to recover a safepoint to the new drive with no luck, same error code as above.
Disappointed to say the least.
What did you find to be the best way to transfer files. The app will not let me multi select folders so it is very slow & tedious. Did you just use Windows Explorer to drag & drop?
I unplugged the USB drive fron the NAS, plugged it in a computer and copied back to the NAS. THis USB+Ethernet was much faster than copying the data from the USB attached to the NAS (which is a very slow connection).