Best / fastest connection between 2 Vero 4k boxes

I have tried to set up both an NFS and FTP connection from the second box to the first one but I get this message with both…

Unable to connect
Couldnt retrieve directory information. This could be due to the network not being connected. Would you like to add it anyway?

I have tried answering this Yes but I then get the message…

Remote Share
Couldnt connect to network server

I have tried setting the Remote Path from being blank to the drive I want to use (/media/Apple TV) but this shows the same messages.

I am a bit stumped at the moment. The only connection type I have successfully created between the 2 boxes is the SFTP one.

Any help would be appreciated.