Two 2003 R2 member servers started to get this error at around the same time: Event Type: Error Event Source: NetBT Event Category: None Event ID: 4321 Date: 6/15/2011 Time: 12:51:22 PM User: N/A Computer: <computer name> Description: The name "<domain name> :1d" could not be registered on the Interface with IP address 10.10.0.12. The machine with the IP address 10.10.0.15 did not allow the name to be claimed by this machine. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp. Data: 0000: 00 00 00 00 04 00 56 00 ......V. 0008: 00 00 00 00 e1 10 00 c0 ....á..À 0010: 01 01 00 00 01 00 00 c0 .......À 0018: 0d 01 00 00 00 00 00 00 ........ 0020: 00 00 00 00 00 00 00 00 ........ 10.10.0.12 is one of the member servers and 10.10.0.15 is a 2003 R2 domain controller. There is also an error on the member server that says it tried to become the master browser but was not able to, so the domain controller is the master browser. We do not use WINS. How can we eliminate this error?

If you disable NetBIOS over TCP/IP within Network Connections on the Network Card does the message stop?

I have not tried to disable NetBIOS. This is a Sharepoint server. Would disabling NetBIOS have any negative impact on Sharepoint or other services on this server? Would it require a reboot?

It should not impact sharepoint and wont require a reboot, worth a try.

Hi, Thank you for your post. Have you tried to force a Browser election on your PDC? However, shutting down and restarting a computer that is configured as the preferred master browse server, or stopping and restarting Computer Browser service on that computer, forces the building of a new browse list. This happens because when a preferred master browse server starts, it forces an election, which it wins. The preferred master browse server has no browse list at startup, so it then forces all members of the domain or workgroup to announce themselves. Best Regards, James

I did reboot the server, but that seemed to cause the error to occur more frequently. What is the procedure to force a Browser election on the domain controller?

Hi, Shutting down and restarting your PDC, or stopping and restarting Computer Browser service on that computer would force an election. Best Regards, James