Microsoft KB Archive/237736

= Incorrect Settings in the Data1 and Data2 Fields in the ADD_NAME_RESPONSE Packet =

Article ID: 237736

Article Last Modified on 2/27/2007

-

APPLIES TO


 * Microsoft Windows 2000 Server
 * Microsoft Windows 2000 Advanced Server
 * Microsoft Windows 2000 Professional Edition

-



This article was previously published under Q237736



SYMPTOMS
When a NetBIOS client attempts to register a unique NetBIOS name, an ADD_NAME_QUERY packet is sent out. If the name is unique, there should be no response for this packet. If a client attempts to register a group NetBIOS name, an ADD_GROUP_NAME_QUERY packet is sent instead. The name does not have to be unique in this case, as multiple clients can join a NetBIOS group. If the unique name or group name already exists, NetBIOS clients respond with an ADD_NAME_RESPONSE packet to indicate that the name is already registered. The client also populates two fields in the response packet to indicate the status of the name. In some cases, Windows 2000 may send incorrect information in these fields.



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.



MORE INFORMATION
The formation of an ADD_NAME_RESPONSE packet is as follows:

NETBIOS: Add Name Response (0x0D) NETBIOS: Length = 44 (0x002C) NETBIOS: Signature = 0xEFFF NETBIOS: Command = Add Name Response (0x0D) NETBIOS: Data1 = 0x00 NETBIOS: Data2 = 0x0000 NETBIOS: Transmit Correlator = 0x0002 NETBIOS: Destination Name = BEETLE        <00> NETBIOS: SMB Name Type = Workstation (00) NETBIOS: Node address = 202020202000 The Data1 and Data2 fields in the ADD_NAME_RESPONSE packet should be set as follows:

Data1 0x00 - Name is already registered 0x01 - Name is in the process of being registered

Data2 0x0000 - Name is registered as a Unique Name 0x0001 - Name is registered as a Group Name

There are two situations in which Windows 2000 responds incorrectly:
 * Windows 2000 always sets the Data1 field to 0x00 even in cases where the name is not yet registered.
 * Windows 2000 will set the Data2 field based on the type of ADD query it received. For example, if an ADD_NAME_QUERY packet is sent and a duplicate name exists, the Data2 packet will be set to 0x0000 regardless of the actual status of the name. The converse is true as well, if an ADD_GROUP_NAME_QUERY is sent, the Data2 response field will be set to 0x0001.

NOTE: Windows 2000 computers will not always respond to these packets, they will only respond if they have registered the NetBIOS name in question.

Additional query words: netbeui tcp/ip

Keywords: kbnetwork kbprb KB237736

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.