NetBT stopped working, half-ways

We have a Win 2003 server, web ed., which has been a domain member
since installation about 7 months ago, and everything has been working
fine.

A weeks ago, user authentication (e.g. ftp logins) stopped working, and
we started to investigate. It was now unable to contact the domain
controller, takes a very long time to browse the microsoft network,
etc.

We left the domain and tried to join again, which results in a message
that the domain controller cannot be contacted, and the recommended
troubleshooting recommends verifying DNS records... but we are using
netbios lookups. However, direct access to a shares on the DC works,
which seems very strange to me.

Other clients can join the domain just fine. We've set up another DC
with a temp domain, other clients can join this one too, but our
problem server can not.

By sniffing the network, we see broadcast queries from the server for
the domain when we try to join, and unicast responses from the DC, but
these seem to be ignored. After some seconds, another query broadcast
is sent, and is replied to, but seemingly ignored. In the case of
working clients, they initiate direct contact after they got the
netbios response.

No firewalls are intervening and everything else works OK (i.e. regular
network connectivity, accessing shares directly by referencing the
server), it just seem to be the netbios lookup protocol that is failing
(UDP, port 138).

We've tried for a week now to solve this, checking security policy
settings, making sure there are no firewalls enabled, changing switch
port, lmhosts hardcoding of server IP and 0x1c records for the domain,
checking the netbios binding order (server is multihomed), various
registry modifications, etc.

Has anyone experienced similar problems? Or has other recommendations?

(E-Mail Removed) wrote:
> We have a Win 2003 server, web ed., which has been a domain member
> since installation about 7 months ago, and everything has been working
> fine.
>
> A weeks ago, user authentication (e.g. ftp logins) stopped working,
> and we started to investigate. It was now unable to contact the domain
> controller, takes a very long time to browse the microsoft network,
> etc.
>
> We left the domain and tried to join again, which results in a message
> that the domain controller cannot be contacted, and the recommended
> troubleshooting recommends verifying DNS records... but we are using
> netbios lookups. However, direct access to a shares on the DC works,
> which seems very strange to me.

Active Directory domains cannot use NetBIOS resolution for Authentication,
NetBIOS resolution is used for Network Places, but Active Directory requires
DNS lookups.
In most cases the Domain Controller is used for Active Directory DNS
resolution, so all domain members would need to use the DC's address for
DNS, only. Do not use any external DNS in TCP/IP Properties that do not
support the AD domain.

--
Best regards,
Kevin D. Goodknecht Sr. [MVP]
Hope This Helps
===================================
When responding to posts, please "Reply to Group"
via your newsreader so that others may learn and
benefit from your issue, to respond directly to
me remove the nospam. from my email address.
===================================
http://www.lonestaramerica.com/
http://support.wftx.us/
http://message.wftx.us/
===================================
Use Outlook Express?... Get OE_Quotefix:
It will strip signature out and more
http://home.in.tum.de/~jain/software/oe-quotefix/
===================================
Keep a back up of your OE settings and folders
with OEBackup:
http://www.oehelp.com/OEBackup/Default.aspx
===================================