Help required: security update to 4.3.8-ubuntu broke domain connection

[Kielbasiewicz, Peter]

This weeks security update broke our samba sharing and I have no clue how to solve it.
Our customized smb.conf doesn't work anymore and the new default config does not list anything for samba servers being just AD clients
We don't use printing through samba nor do we have any passwords with samba.
We use a users.map though to map domain users to our local linux accounts.

We used to use the smb.conf shown below but after the update we get error messages
  domain_client_validate: Domain password server not available.

What should be adapted to get samba working again?

[global]
  debug level = 0
  syslog      = 0
  oplocks        = False
  level2 oplocks = False
  kernel oplocks = false
   workgroup = companyAD
   security = DOMAIN
   password server = *
   encrypt passwords = yes
   browse list = no
   browseable  = no
   wins server = d....001
  local master = no
  log file = /var/log/samba/log.%m
   max log size = 50
   lock directory = /var/lock/samba/locks
   guest account = smbguest
   map to guest  = Never
   username map = /etc/samba/users.map
   create mask = 0644
   force directory mode = 0775
   directory mask = 0775
   dead time = 240
   dos filetime resolution = true
   server string = Linux Samba %v
   printing      = bsd
   printcap name = /dev/null
unix extensions = no
  include = /etc/samba/shares.conf

--
With kind regards,

Peter Kielbasiewicz
Business Process Engineer
IT4R&D | Philips IT Infrastructure

Philips Medizin Systeme Böblingen GmbH, Hewlett-Packard-Strasse 2, 71034 Boeblingen, Germany
Tel: +49 (0)7031/463-1893, Fax: +49 (0)7031/463-1175
Email: peter.kielbasiewicz at philips.com<mailto:peter.kielbasiewicz at philips.com>
www.philips.com/healthcare<http://www.philips.com/healthcare>

Geschäftsführer: Dr. Werner Haas (Sprecher), Dieter Haase, Klaus Baumann
Sitz der Gesellschaft: Böblingen | Registergericht Stuttgart, HRB 245187


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