TCP/IP Troubleshooting

Removing and Reinstalling TCP/IP

When you attempt to reinstall a TCP/IP service, you might receive a "The registry subkey already exists" error message. To correct this problem, you should ensure that all the components of a given TCP/IP service are properly removed and then remove the appropriate registry subkeys.

Caution

Do not use a registry editor to edit the registry directly unless you have no alternative. The registry editors bypass the standard safeguards provided by administrative tools. These safeguards prevent you from entering conflicting settings or settings that are likely to degrade performance or damage your system. Editing the registry directly can have serious, unexpected consequences that can prevent the system from starting and require that you reinstall Windows 2000. To configure or customize Windows 2000, use the programs in Control Panel or Microsoft Management Console (MMC) whenever possible.

If you removed TCP/IP and its related service components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NetBT

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TcpipCU

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dhcp

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LmHosts

SNMP Registry Keys

If you removed the SNMP service components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\RFC1156Agent

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Snmp

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Snmp

TCP/IP Printing Registry Keys

If you removed the TCP/IP Printing service components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Lpdsvc

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TcpPrint

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ LpdsvcSimple TCP/IP Services

Simple TCP/IP Services Registry Keys

If you removed the Simple TCP/IP Services components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SimpTcp

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SimpTcp

DHCP Registry Keys

If you removed the DHCP service components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DhcpMibAgent

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DhcpServer

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\DhcpServer

WINS Registry Keys

If you removed the WINS service components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Wins

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WinsMibAgent

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Wins

DNS Registry Keys

If you have removed the DNS service components, you must also remove the following registry subkeys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dns

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DnsMibAgent

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dns