I tried to copy a folder structure (located on a NetApps filer) to the N5200Pro using robocopy.exe (from W2K3 ressource kit) and got the error 282 (0x0000011A) "The mounted file system does not support extended attributes". I even tried the switches /COPY: DT (copy only data and timestamps, no NTFS ACLs, no file ownership info, no attributes) plus /A-:RASHNT (turn off all attributes in copied files) but no luck.
With copy & paste in Windows Explorer it was possible to copy the folders...?!