Files view as directories under Nautilus and Samba

Hi,

The "box" of my Internet provider can also be used as a NAS and works on Samba 3.0.37.

And I have this strange behaviour since end of January : I access to a shared directory of this NAS thru Nautilus, I can see the content but the files are parsed as directory. Sometimes, when I refresh the content, Nautilus ends up recognizing it as a file, but when I try to open it tells me " This is not a directory ".

Initially I had this in my smb.conf (as seen in the doc) :
client ipc min protocol = NT1
client min protocol = NT1
client ipc max protocol = NT1
client max protocol = NT1
server min protocol = NT1
server max protocol = NT1

I try to put only (as seen in this issue) :
protocol = SMB3

It didn't work and now I have :
workgroup = WORKGROUP
client ipc min protocol = NT1
client ipc max protocol = SMB3
client min protocol = NT1
client max protocol = SMB3
server min protocol = NT1
server max protocol = SMB3

I have no access problems but I still have issue to see my files as such.

Any idea ?