[Samba] Incompatibility Windows 7

[Sonic]

In case this helps here's some smb.conf parameters (many not at the
defaults) being used in a shop where most clients are Windows 7 domain
members. There is one XP domain member and also one NT4 Server domain
member (was the original PDC) running Exchange 5.5. All systems work
just superb. No changes to min/max protocols.

The Samba member server (handles all file and print sharing):
================================
server role = MEMBER SERVER
security = domain
smb ports = 445 139
client ipc signing = Auto
client signing = Auto
server signing = Auto
raw NTLMv2 auth = Yes
ntlm auth = Yes
wins server = <ip address of PDC>
================================

The PDC (no file or print sharing, only a PDC running in an LXC):
================================
server role = CLASSIC PRIMARY DOMAIN CONTROLLER
security = user
smb ports = 445 139
raw NTLMv2 auth = Yes
ntlm auth = Yes
client use spnego = No
wins support = yes
================================

As you're not trying to support NT4 you may not need to go to the
extremes I show, but it's nice to know it works.

Both above are Samba 4.6.5 compiled from source running on Debian Stretch.

In regards to the NT_STATUS_NO_LOGON_SERVERS error rejoining the
domain from the afflicted servers may help. Also check that your WINS
support is properly setup.

Chris