The Scope ID option in the TCP/IP configuration provides a way to isolate a group of computers that only communicate with each other. The Scope ID is a character string value that is appended to the NetBIOS name and is used for all NetBIOS over TCP/IP communications from that computer. Other computers that are configured with an identical Scope ID are able to communicate with this computer, while TCP/IP clients with a different Scope ID disregard packets from any other Scope ID.

In situations where troubleshooting TCP/IP connectivity is required, this value should be checked on both the client and the server (or client to client) computers to ensure that the Scope ID is identical. For example, when a domain logon is attempted from a client computer, the Scope ID is appended to the name of the domain as it is broadcast, and only domain controllers listening for the same Scope ID are able to respond to the request.

Additionally, the Scope ID is case-sensitive, so computers configured with the Scope ID "scope" attempting to communicate with computers with Scope ID "SCOPE" will be unable to communicate via NetBIOS over TCP/IP. For Microsoft Windows 95 and Windows NT 4.0, the Scope ID configuration can be found on the "WINS Configuration" tab in the properties for TCP/IP in the Network section of Control Panel. In Windows for Workgroups and Windows NT 3.x, this can be configured from the Advanced options in the TCP/IP configuration dialog box in the Networks section of Control Panel. NOTE: You can still have non-NetBIOS communication with a computer with a different scope id. Thus, you are able to ping, but error 53 appears (network name not found) if you attempted to use NET VIEW to view the computer.