Error Message When Installing TCP/IP or Adding TCP/IP Service

• Microsoft Windows NT Workstation versions 3.5, 3.51, and 4.0
• Microsoft Windows NT Server versions 3.5, 3.51, and 4.0

SYMPTOMS

When you attempt to reinstall TCP/IP or add a TCP/IP service, you may receive one or more of the following error messages:

• Registry service subkey already exists

  -or-

• Unable to remove name space provider

RESOLUTION

To correct this problem, ensure all the components of a given TCP/IP Service are properly removed, and then ensure the following registry subkeys are also removed before you reboot the computer:

IMPORTANT: If you have Windows NT 4.0 with Service Pack 2, see the following article in the Microsoft Knowledge Base before removing any registry keys:

   ARTICLE-ID: Q162837
   TITLE     : Replacing TCPIP after SP2 causes STOP 0x00000050

NOTE: You may or may not have all of the following Registry entries Depending on your TCP/IP configuration.

NOTE: CCS=CurrentControlSet

HKEY_LOCAL_MACHINE\Software\Microsoft\DhcpMibAgent HKEY_LOCAL_MACHINE\Software\Microsoft\DhcpServer HKEY_LOCAL_MACHINE\Software\Microsoft\FTPSVC HKEY_LOCAL_MACHINE\Software\Microsoft\LPDSVC HKEY_LOCAL_MACHINE\Software\Microsoft\NetBT HKEY_LOCAL_MACHINE\Software\Microsoft\RFC1156Agent HKEY_LOCAL_MACHINE\Software\Microsoft\SNMP HKEY_LOCAL_MACHINE\Software\Microsoft\SimpTcp HKEY_LOCAL_MACHINE\Software\Microsoft\Tcpip HKEY_LOCAL_MACHINE\Software\Microsoft\TcpipCU HKEY_LOCAL_MACHINE\Software\Microsoft\TcpPrint HKEY_LOCAL_MACHINE\Software\Microsoft\Wins HKEY_LOCAL_MACHINE\Software\Microsoft\WinsMibAgent

HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\DHCP HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\DhcpServer HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\FTPSVC HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\Lmhosts HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\LPDSVC HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\NetBT HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\SimpTcp HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\SNMP HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\Tcpip HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\Wins HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\WinSock HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\WinSock2 HKEY_LOCAL_MACHINE\SYSTEM\CCS\Services\'NetDriver'x\Parameters\Tcpip

    where NetDriver is the name of network card installed on system and
    where x is the number of the network adapter.

HKEY_LOCAL_MACHINE\System\CCS\Enum\Root\Legacy_DHCP HKEY_LOCAL_MACHINE\System\CCS\Enum\Root\Legacy_Lmhosts HKEY_LOCAL_MACHINE\System\CCS\Enum\Root\Legacy_LPDSVC HKEY_LOCAL_MACHINE\System\CCS\Enum\Root\Legacy_NetBT HKEY_LOCAL_MACHINE\System\CCS\Enum\Root\Legacy_TCPIP HKEY_LOCAL_MACHINE\System\CCS\Services\LanManServer\Linkage\Bind HKEY_LOCAL_MACHINE\System\CCS\Services\LanManWorkstation\Linkage\Bind

NOTE: Removing these additional keys requires manipulation of the rights on those keys. The default rights for Everyone is READ. To change the rights, log on as Administrator, take ownership of the keys (Legacy_NETBT and Legacy_TCPIP), and then give Full Control to Everyone (NOTE: You may need to select Replace permission on existing subkey). After giving Full Control to Everyone, you can delete the key and continue with the protocol installation. Reboot the computer so that Registry changes are recognized by Windows NT.