Duplicate Name on the Network error message

 -Microsoft Windows NT Server versions 3.5 and 3.51
 -Microsoft Windows NT Workstation 3.5 and 3.51

SYMPTOMS

A DHCP client receives a "Duplicate name on the network" error message when logging on to the network.

Also, the Enable IP Routing check box in the TCP/IP properties of the Network Control Panel tool is checked, but is unavailable and cannot be cleared.

CAUSE

If Remote Access Service (RAS) has been installed, in addition to another network protocol, and then removed or disabled, the registry entries may not be automatically removed.

RESOLUTION

WARNING: Using Registry Editor incorrectly can cause serious, system-wide problems that may require you to reinstall Windows NT to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.

1. If RAS is still installed, remove it using the Network Control Panel tool, under Installed Network Software.

2. Start Registry Editor (Regedt32.exe) and go to the following subkey:

   \HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services \Tcpip\Parameters

3. Change the 'EnableIpRouting' value to 0.

4. Restart the computer.

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 3.5 and 3.51. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.