Client Cannot Find New System When NetBIOS Name Is Removed and Reregistered

The NetBIOS functionality enables client computers to register more than one NetBIOS name. If the NetBIOS name is unregistered by one system, and then registered by another system, the Windows 2000-based client does not find the new system that registered the name if the Windows 2000-based client has already resolved the NetBIOS name.

This issue occurs because Windows 2000-based clients do not clear the NetBIOS over TCP/IP (NBT) name cache after they receive a negative session response from a server. This behavior causes the Windows 2000 clients to attempt to connect to the server that had the name registered the first time the name was resolved to an IP address.

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To resolve this issue, add or change the following registry value on the client computer:

1. Start Registry Editor (Regedt32.exe).
2. Locate the following key in the registry:
   HKEY_LOCAL_MACHINE\CurrentControlSet\System\Services\netbt\parameters
3. On the Edit menu, click Add Value, and then add the following registry value:
   Value Name: TryAllNameServers
   Data Type: REG_DWORD
   Value: 1
4. Quit Registry Editor.

You can use the nbtstat -R command to manually clear the NBT cache.

The following sequence demonstrates the issue described in the "Summary" section:

1. Create a directory share named "Test" on both ServerA and ServerB.
2. Register "Vcom" as an additional NetBIOS name on ServerA by using the NetServerComputerNameAdd() API.
3. On a Windows 2000-based client, run the following command: dir \\vcom\test. This command completes successfully.
4. Delete the "Vcom" NetBIOS name on ServerA by using the NetServerComputerNameDel() API.
5. Register the NetBIOS name "Vcom" on ServerB by using the NetServerComputerNameAdd() API.
6. On the Windows 2000-based client, run the following command: dir \\vcom\test. The command does not complete successfully.