In Windows XP, the uninstall button is disabled for the TCP/IP protocol. The TCP/IP stack is considered a core component of the operating system, and it is not possible to uninstall it. Still, in some extreme cases, the most appropriate solution is to reset the TCP/IP stack back to a default state...

There is a NetShell (netsh) command-line scripting utility for the configuring and monitoring of Windows XP networking. Using this tool, a reset command is available that rewrites pertinent TCP/IP registry keys to achieve the same result as the removal and the reinstallation of the protocol. The following registry branches are reset using this tool:

SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\
SYSTEM\CurrentControlSet\Services\DHCP\Parameters\

Comand usage

Simply type the following in Command Prompt:

netsh int ip reset c:\resetlog.txt

"c:\resetlog.txt" being the logfile generated by netsh to store changes being made. If the file exists, the new log will be appended to the end of the existing file.