[Samba] Frustrated with "network name is no longer available"

[Morgan Toal]

Nothing fancy, and I've done this before...

but today I'm trying to get samba 3.10.5 with tdbsam working on Centos 6.3.

iptables is stopped on the samba server.
selinux is disabled on the samba server.
service smb and nmb are running.
samba server has an 'a' record on our dns server.
samba server is set to be a wins server.

Note- I have ANOTHER wins server on the same subnet for another samba 
server.
(the other one is production, the one i am setting up is it's replacement)

I have two windows 7 sp1 clients.
The registry settings in the samba-windows7 howto are applied to these 
machines.
both windows 7 clients are hard-coded to use our new centos 6.3 samba 
server for WINS.
both windows 7 clients were successfully joined to the domain.
One can log in as a domain user just fine.

The other gives "The specified network name is no longer available" when 
trying to log in to the domain
when logged into the problem machine as local admin, I can "net use" the 
samba server no problems.

I am thinking this means some sort of name resolution issue... but I am 
simply out of ideas.

I've gone over lots of forum and list postings, but there is simply no 
definitive answer to this issue.

!!! This shouldn't be this hard! I've done it before! What am I missing ???

here's the global section of my smb.conf
It was copied from a working configuration on another server
(workgroup and netbios names changed of course)

[global]
netbios name = city1
workgroup = city
smb ports = 139
passdb backend = tdbsam
security = user
printcap name = cups
add user script = /usr/sbin/useradd -m %u
add group script = /usr/sbin/groupadd %g
delete user script = /usr/sbin/userdel -r %u
delete group script = /usr/sbin/groupdel %g
add user to group script = /usr/sbin/usermod -G %g %u
add machine script = /usr/sbin/useradd -s /bin/false -d /dev/null %u
logon script = logon.bat
logon drive = Z:
logon home = \\%L\%U
domain logons = Yes
os level = 35
preferred master = Yes
domain master = Yes
local master = yes
printing = cups
wins support = yes
host msdfs = yes
server signing = auto
browsable = yes
guest account = nobody
encrypt passwords = yes
domain logons = yes