Re: NetBios Names and SP2

From: Bruce Sanderson (bsanders_at_junk.junk)
Date: 12/05/04


Date: Sat, 4 Dec 2004 16:31:05 -0800

1.Run the command:

   netsh firewall show state

This will tell you which ports are open in the firewall as well as some
other information.

2. Run the command (note: you must have the Support Tools from the Windows
XP CD installed):

   browstat view 1

This will tell you what NetBIOS names are currently known to your computer.
You should see other computers on the LAN listed as well as the one from
which you run the command

For example:

Remoting NetServerEnum to \\CRRTM on transport
\Device\NetBT_Tcpip_{C5A8F0D3-32A
F-4431-9410-407F9EE4F66F} with flags ffffffff
2 entries returned. 2 total. 10 milliseconds

\\COMPUTERROOM NT 05.01 (W,S,PQ,NT,PBR)
\\CRRTM NT 05.02 (W,S,PDC,TS,PQ,NT,MBR,DFS)

3. Check that "Enable NetBIOS over TCP/IP" is selected in the network
connection's Properties, Internet Protocol (TCP/IP), Properties, Advanced,
WINS panel.

4. Check that the Computer Browser service is running.

5. The command

   netstat -a -o -n

will tell you which ports have been opened for listening, although the
firewall may block incoming connection requests to some of those ports, at
least from some IP addresses.

6. Part of the configuration for firewall Exceptions, is the "Scope". You
will probably find that the "Scope" for the "File and Print Sharing"
exception is "My network (subnet) only", which is probably why
www.hackercheck.com reports port 445 as closed.

7. When I run the netsh command from above on my computer, I get this
result:
Firewall status:
-------------------------------------------------------------------
Profile = Standard
Operational mode = Enable
Exception mode = Enable
Multicast/broadcast response mode = Enable
Notification mode = Enable
Group policy version = None
Remote admin mode = Disable

Ports currently open on all network interfaces:
Port Protocol Version Program
-------------------------------------------------------------------
135 TCP IPv4 (null)
137 UDP IPv4 (null)
139 TCP IPv4 (null)
138 UDP IPv4 (null)
3389 TCP IPv4 (null)
445 TCP IPv4 (null)

--------------------------------------------------

TCP Ports 139 and 445, UDP ports 137 and 138 are opened by the File and
Print Sharing exception.
TCP Port 135 is opened by an Exception I added to allow incoming Offered
Remote Assistance connections (see
http://support.microsoft.com/?kbid=555179).
TCP Port 3389 is opened by the Remote Desktop exception.

With these exceptions, communication with other Windows XP SP2 and Windows
Server 2003 computers on this my home network, by NetBIOS name, works and
the computer names show up in the browse list (My Network Places, Entire
Network, Microsoft Windows Network).

-- 
Bruce Sanderson  MVP
It is perfectly useless to know the right answer to the wrong question.
"SalamOnAltern" <salam@altern.org> wrote in message 
news:eKaoPc$xEHA.4028@TK2MSFTNGP09.phx.gbl...
> Also, I made a test (from my laptop not the machine wher I have my DSL 
> connection) using the service provided on www.hackercheck.com web site for 
> security tests, the outcome of the test indicate the following
>
> Open ports:
> Closed ports: 53, 25, 22, 80, 21
> Not responding ports: 3128, 5900-5910, 500, 445, 443, 8080, 8787, 113, 
> 54320, 12345, 143, 139, 79, 23, 110, 138, 137, 135, 119
>
> Which means 445 port can not respond (which is used in Netbios over TCP) 
> if I am not mistaken. This is in spite of the fact that in the firewall 
> exception, file and printing is checked
>
> Salam
> "Robert L [MS-MVP]" <noreply@hotmail.com> wrote in message 
> news:uYtlCAExEHA.2540@TK2MSFTNGP09.phx.gbl...
>> with icf enabled, can you ping each other?
>>
>> -- 
>> For more and other information, go to  http://www.ChicagoTech.net
>>
>> Don't send e-mail or reply to me except you need consulting services. 
>> Posting on MS newsgroup will benefit all readers and you may get more 
>> help.
>>
>> Bob Lin, MS-MVP, MCSE & CNE
>> Networking, Internet, Routing, VPN, Anti-Virus, Tips & Troubleshooting on 
>> http://www.ChicagoTech.net
>> Networking Solutions, http://www.chicagotech.net/networksolutions.htm
>> VPN Solutions, http://www.chicagotech.net/vpnsolutions.htm
>> VPN Process and Error Analysis, 
>> http://www.chicagotech.net/VPN%20process.htm
>> VPN Troubleshooting, http://www.chicagotech.net/vpn.htm
>> This posting is provided "AS IS" with no warranties.
>> "SalamOnAltern" <salam@altern.org> wrote in message 
>> news:%232xRPlDxEHA.1452@TK2MSFTNGP11.phx.gbl...
>>> Hi,
>>> I have a small network with 4 computers (2 win2K, 1 win2003 and a laptop
>>> running XP SP2)
>>> one of the 2K is my gateway to internet and acts a s a dhcp for the rest
>>> (using the network 192.168.......)=
>>> Before SP2, I ll machines connect to each other using computer names. 
>>> Since
>>> SP2 and it's firewall, when firewall is active, I can not connect to 
>>> other
>>> machines from my laptops to other machines nor the other machines see my
>>> laptop. I need to use IP addresses.
>>> When I desactivate the firewall, everything goes Ok and I can connect 
>>> using
>>> netbios names
>>> I checked the firewall config, in exception tab there is the file and
>>> printer sharing enabled with all necessary ports (default config which I
>>> never played with)
>>> Should I do or add something else in order to be able to use netbios 
>>> names?
>>> N.B : Even TCP/IP netbios helper is enabled.
>>>
>>> Thanks in advance
>>>
>>>
>>
>>
>
> 


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