USB storage on MyBookLiveDuo shows only 79GB capacity over LAN instead of 2TB

Something is telling me that the reason why 2TB WD Book Essential is showing only 79GB capacity over my LAN is because MyBookLiveDuo is not NTFS but some other weird file system. This might be a valid explanation for support people but certainly not acceptable for the end user.

How can I attach the 2TB WD Essentials dive to WDMyBookLiveDuo and use its full capacity over LAN?

I’ll bet 79G is also the free space of your C drive?
Also, the file system is irrelevant on NAS drives.