NT master browsers conflict

Hi everyone,

We are having some big problems with the operation of
our network which was working perfectly until we added
a Win2000 workstation computer to it. Now our NT4 PDC
server is going nuts and throwing up errors and the
whole network has slowed to a crawl with connections
being lost and just today the exchange server gave up
and stopped accepting connections.

I have not changed anything in any way on the server
in the past few months so I can only think that these
errors must be with the Win2000 machine and the way it is
interacting with the network and server.

When I am using the Win2000 PC I keep getting an error
every now and then when I try and go to a network drive
which says:

"an error occurred while reconnecting S: to \\classlink\saj
Microsoft windows network: The local device name is already in use.
This connection has not been restored."

(classlink is the name of our PDC)
When this happens I can't access the drive but it then
starts working again 10 secs later and I can access the
net drive again.

I get these problems whether I login to the machine on the
main domain "class" or on the "ISIS" which is the name
of the win2000 workstation.

I checked event viewer on the PDC and on the win2000 PC
and the following errors occurred (PDC errors listed 1st):

The master browser has received a server announcement from the computer ISIS that

believes that it is the master browser for the domain on transport NetBT_E100B1.

The master browser is stopping or an election is being forced.

The browser has forced an election on network \Device\NwlnkIpx because a master

browser was stopped.

The browser has forced an election on network \Device\NwlnkNb because a Windows NT

Server (or domain master) browser is started.

The session setup from the computer ISIS failed to authenticate. The name of the

account referenced in the security database is ISIS$.  The following error

Access is denied.  

A SAP announcement was sent over \Device\NwlnkIpx which is configured for multiple

networks, but no internal network is configured. This may prevent machines on some

networks from locating the advertised service.

..And these are the errors on the win2000 PC:

No Windows NT or Windows 2000 Domain Controller is available for domain CLASS. The

following error occurred:
The RPC server is unavailable.  

The browser was unable to retrieve a list of servers from the browser master

\\CLASSLINK on the network

\Device\NetBT_Tcpip_{42951F65-4D3D-4056-86E5-17CE64CC0D61}. The data is the error

The browser has received a server announcement indicating that the computer ISIS

is a master browser, but this computer is not a master browser.

The master browser has received a server announcement from the computer CLASSLINK

that believes that it is the master browser for the domain on transport

NetBT_Tcpip_{42951F65-4D3D-4056. The master browser is stopping or an election is
being forced.

The browser was unable to retrieve a list of servers from the browser master

\\CLASSLINK on the network

\Device\NetBT_Tcpip_{42951F65-4D3D-4056-86E5-17CE64CC0D61}. The data is the error

Windows cannot unload your registry file.  If you have a roaming profile, your
settings are not replicated. Contact your administrator.  
DETAIL - Access is denied. , Build number ((2195)).

One final note - both machines in question have two net
cards in them so they can operate in either the private
IP range or the public internet IP range.

If anyone can tell me what is going on here then I would
much appreciate it!

Who is Participating?
NenadicConnect With a Mentor Commented:
That is the message that appears when you specify MaintainServerList=NO in the Registry. Completely expected.
Prevent Browser Service on Windows 2000 from competing to become Master Browser.

Open up the Registry on Win2000 using REGEDT32.

There should be two parameters: IsDomainMaster and MaintainServerList.
They should look like this originally:

Double-click on MaintainServerList and change the value to NO

That should hopefully solve the problem. If it persists, we'll go into examining the two network cards, which could relate to Workstation Service. Later on that.
Make sure you restart your Windows 2000 Professional in order to reload the Registry.

While at it - confirm that the MaintainServerList parameter on your PDC is set to YES value. If not - change it.
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kcs_tecAuthor Commented:
Thankyou Nenadic for your comment.

I have changed the registry entry that you suggested and
rebooted the machine.  I will wait a bit and see what
happens now. The PDC already had the correct serverlist
entry so I left that as it is, although I was wondering
if the PDC entry for "isdomainmaster" should be set to
TRUE as it is currently on false...?

I am a little unsure if this one entry is the cause of all
these network problems we are having. Are there any other
things which we should be looking at as well?

I mean, will this setting we have just changed fix the
errors pertaining to the reconnecting of the net drives
and the "no rpc server is available".?

Thanks again for your help.
Quite possibly, it will. Browser Service is used for finding resources, PDC, domains etc.

If Windows 2000 computer was disturbing the PDC from maintaing the list, other computers on the network could have been experiencing problems with authentication, connecting to resources (RPC) and generally browsing the network.

Finally, if the problem is not solved, have a look at the following article from Microsoft, regarding Master Browsers on computers with two NICs:
kcs_tecAuthor Commented:
Again many thanks Nenadic.

The drive mapping errors seem to have gone away now, though
I'm going to wait a day or so to see if this has solved
the other errors with Win95 machines working very slowly
when it comes to getting network resources from the the
PDC. Also the exchange server seeem to be ok now after we
rebooted the server.

I checked the MS KB article you mentioned and it does seem
very relevant to some aspects of how our server is setup,
however I'm a bit confused about what I need to do. The
article said that the PDC must not be multimhomed for
browser service to work properly. So how has it been
working so far?  We have always been able to browse from
any PC's network resources to any other's.

It's extraordinary how many things one can still learn
despite being an I.T technician for 3 years. I have setup
so many NT servers and yet still never got round to
finding out what all the services do such as RPC/DDE/
Browser/index etc..

I wish I still had enough points left to submit a question
asking someone to describe what some of these other
services are doing which are running on the PDC:


200 is quite a few points, so I'll help out a bit on services: :-)

CSRSS (not CRSS) is Client Server Subsystem or Win32 subsystem. This is the portion of OS that allows Microsoft-based applications (32-bit, 16-bit and DOS) to interact with OS in order to use resources (memory, disks, printers and alike)

InetInfo is the service (process) that houses WWW, FTP and other IIS services.

LSASS is Local Security Authority that is used to query local security database in order to authenticate users. used both for logons and for access to resources.

Locator is used by Netlogon service to find Domain Controllers (WINS, broadcast etc.) to get authenticated.

MSPAdmin is Microsoft Proxy Administrator service, interacts with IIS and other Proxy services - WSP and WebProxy.

nhsrvice - dunno

RPCSS is Remote Procedure Call Server Service. Used for just about any network connection between computers - authentication, drive mapping, messaging, intra-domain trust (trust between DCs and workstations, for example)

SMSS - Session Manager. Used to maintain connection between two Windows computers - proper data to go to proper applications - i.e. prevent web page from going to email client, for example.
kcs_tecAuthor Commented:
It was very informative to read your description of the
services I mentioned.  If only MS would think to put info
like that in their NT helpfile in windows.

Things seem to be running much more smoothly now on our
network so I will leave things for another day and then
assign you the points Nenadic.

There is one small thing that I am a little unsure on and
I know it shows great ignorance on my part, but how does
WINS affect all of this which we have been dealing with
today?  I checked on the server and WINS seems to be all
up and running and the win95 clients are using DHCP for
WINS resolution, but is WINS a vitally necessary thing to
have - is it making the system more efficient or is it
just making things more complex and slower? The only
placees where settings on machines need a network name
I have always used the IP address.

WINS is also used to provide connectivity for domains (domain lists), messaging (usernames are registered via WINS). If everything is running smoothly - leave WINS as is. It is a useful service. Once you switch (if you do) to Windows 2000, WINS becomes obsolete, as Win200 relies on Dynamic DNS.
kcs_tecAuthor Commented:
I checked in event viewer and the following error
appears a couple of times:

"The Computer Browser service terminated with service-specific error 2550"
Everything seems to be working fine aside from this.

kcs_tecAuthor Commented:
Right, looks like we have a perfect solution here to
this problem and to say that I'm happy now would be
an understatement after all the stress that Win2k
has caused me.

Thankyou very much for your excellent help Nenadic, I
will now close this question and assign you the points.
Thank you. Glad to be of service.
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