In Windows 95 and 98, to check if TCP/IP is installed on your computer, go to Network in the Control Panel. If the protocol is installed, it should be listed under the installed Local Area Network properties. If not, you need to reinstall it by clicking the Add button. Select “Microsoft” as the manufacturer, and under the network protocol, select the TCP/IP protocol. You’ll need to reboot the system.
If you’re using Windows ME/2000/XP, go to Control Panel > Network and Dial-up connections > Local Area Connection. Here, go to Properties. If the protocol is installed, it should be listed under the network adaptor properties. It is important to note here that a network adaptor is different from a dial-up adaptor. The dial-up adaptor gives you access to the Internet, and not to the LAN. If you don’t see the TCP/IP protocol here, click the Add or Install button, select the protocol and click OK. Once installed, you will need to reboot your system for the changes to take effect.