After upgrade to Ubuntu Gnome 16.04, I can no longer access my networked media tank's smb share. It's an old (2009) Popcorn Hour A-110.
When I connect to server smb://192.168.0.5 in nautilus, I get in an endless loop prompted for login resulting in an authentication failed message. I am certain that username/password are correct, because it works in Windows and I've reset it a dozen times. Note that prior to the upgrade (Ubuntu Gnome 15.10), I would not even be prompted for a username/password, it would just open in the file browser.
So I installed smbclient to see what is going on, and that gives me a hint:
smbclient //192.168.0.5/share -U nmt Server does not support EXTENDED_SECURITY but 'client use spnego = yes and 'client ntlmv2 auth = yes' session setup failed: NT_STATUS_ACCESS_DENIED
That seems to suggest that the nmt server might be too old to support some security scheme that is required by the client.
How can I fix this?