If having a laptop which you use in different networks (Home, Work, Customer, etc.), then one can use NetShell to backup each network configuration and restore them again at will. NetShell replaces Routemon from WinNT4.

To backup a configuration :

netsh -c interface dump > c:\configs\officeinterface.txt

To restore a configuration :

netsh -f c:\configs\officeinterface.txt

When using NetShell to change network settings it doesn't require a reboot. One can also use hardware profiles to save the network configuration, but it will require a reboot to change from one hardware profile to another.

Repair/reinit the TCP/IP protocol if it has gone bad (Useful as WinXP cannot uninstall the TCPIP stack):

netsh int ip reset

More info MS KB299357

Repair/re-init the Winsock interface if it has gone bad (Available in WinXP SP2 and Win2k3 SP1):

netsh winsock reset

More info Repair Winsock and TCP/IP in WinXP/Win2k3 (MS KB811259)
More info Repair Winsock and TCP/IP in Win2k (MS KB837333)
More info Repair network for a Win2k Domain Controller (MS KB299451)
More info Repair network for a Win2k3 Domain Controller (MS KB325356)

Note WinXP includes an option called Alternative Configuration, which is used when in a network without an available DHCP server, without needing to fiddle with netsh.

• On the Start-menu, click Control Panel.
• Click Network and Internet Connections and click Network Connections.
• Right-click the wanted connection and select Properties.
• Select Internet Protocol (TCP/IP) and press Properties.
• If the normal configuration is DHCP, then the Alternate Configuration-tab should be available. More info MS KB283676

More info How to Use the Netsh.exe Tool and Command-Line Switches (MS KB242468)
More info Using NETSH to Change from Static IP to DHCP in Windows 2000 - (MS KB257748)
More info NetSh Dump Does Not Completely Configure and Enable the RRAS (MS KB254249)
More info How to Use the Netsh Utility to Export and Import DHCP Scopes (MS KB281626)

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