TCP/IP database files

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

TCP/IP database files

The following table lists the UNIX-style database files that are stored in the systemroot\System32\Drivers\Etc folder corresponding to TCP/IP for computers running Windows ServerĀ 2003 operating systems.

File name Use


Provides host name-to-IP address resolution for Windows Sockets programs.


Provides NetBIOS name-to-IP address resolution for Windows-based networking.


Provides network name-to-network ID resolution for Windows Sockets programs.


Provides protocol name-to-protocol ID resolution for Windows Sockets programs.


Provides service name-to-port ID resolution for Windows Sockets programs.

To troubleshoot any of these files on a local computer, do the following:

  1. Make sure the format of entries in each file matches the format defined in the sample file originally provided with TCP/IP.

  2. Check for spelling errors.

  3. Check for invalid IP addresses and identifiers.


  • By default, the Lmhosts file does not exist. There is an Lmhosts.sam sample file that you can use as a basis for creating an Lmhosts file.