You were not connected because a duplicate name exists on the network.

is that Domain controler with Clients network ?
whats client and server OS ?

I think DNS will not slove this this kind of NetBIOS name conflicts.

*if ur system is  a domain than add client PC  again domain
first logon to server -> Administrative tool ->select  Active Directory Users and Computers -> Computers" OU  locate the entry of Workstation name ( conflict client)> select delete
next  add client  again to domain

*or this could be a service pack issue with Windows 2000 . add latest service pack

The Clients range from 98 - XP and the servers are W2K sp4.  It doesn't matter what name I create as a second host name or what server IP I point to, I get that error and others.  I put an entry in my local hosts file, with a made up name, and I can ping it but get access denied when I try to due anything else to it.  I guess the real ??? is; How can I add a second, third, fourth hostname pointing to an existing server IP address in DNS or ???  I need to be able to access the same server with the same IP address with different names.

is that a domain or work group ?

what U mean by this ??
"I need to be able to access the same server with the same IP address with different names. "

but  in microsoft network  couldnt be same ip address twice or same netbios name twice..

anyway to access  server with diffrent workstation ( diffrent ip and  diffrent  netbios names )

firts  enable NBTas above    SystmProg    comment   ( Net BIOS over tcp/ip).  net connectin properties > TCP/IP properties> advanced > WINS > enable  netbios over TCP/IP.

* if any firewall install ( or personal firewall) on server or client  first disable and check. or configure it  for  network

*if  U can install  WINS then it will resolve this problem

* check each PC computer browser service started. if not then start it  and st it as Automatic  start( administrative tools > services > Computer browser service

Ok, do I get the 100 points for answering my own Question?  I spent more time on Google and found something that work three times for me already.  The answer is in KB-281308 it is a reg hack and requires a reboot.  The artical was last updated on 10/26/05 (is that why I didn't see it before?) and says that it was first fixed in SP3.  Well it looks like they broke it again in SP4. The entry value name equals "DisableStrictNameCheking".  Any rate I have another one that is stumping us that you guys can help with. Thanks for your input on this one.

Did U bind any  network adaptor ( ADSL,VPN) to server that route to Internet or other LAN or WAN connection . some time  this  could be the reson.  Remove the "Client for Microsoft Networks" and "File and Print Sharing .."  that bind to those adaptors.

I made no changes other then the reg. hack.  By the way, the reg. hack needed to be applied to the target servers where the second host name was pointing to.  I will make the change to all servers for my future needs. Thanks again for the help...  

Apply the following registry change to the server. To do so:
Start Registry Editor (Regedt32.exe).
Locate and click the following key in the registry:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\LanmanServer\Parameters

On the Edit menu, click Add Value, and then add the following registry value:
Value name: DisableStrictNameChecking
Data type: REG_DWORD
Radix: Decimal
Value: 1

Quit Registry Editor.
Restart your computer.
 

Such language is certainly uncalled for and very UNprofessional. The answer was given about 3 commenta above. Be a little more patient and thorough next time, please. The OP was unaware of the proper procedures for closing out a question.