All computers on your network must be configured to obtain their network configurations automatically from a DHCP server (which is your router). This is the default Windows configuration, but is always good to check if your computers are correctly configured.

To configure your computers, click on Start, Control Panel, Network Connections, the screen shown on Figure 9 will appear. Right click the network card that will be used to connect this PC to your network and then choose Properties: if this computer is connected to the router using a regular network cable, then the network card we are talking about is the one connected to your router; if this computer will be connected to the router wirelessly, then the network card we are talking about is the wireless network card.

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Figure 9: Network connections.

The screen shown on Figure 10 will appear. Double click on Internet Protocol (TCP/IP) and the screen shown on Figure 11 will show up.

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Figure 10: Network card properties.

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Figure 11: TCP/IP configuration.

On this screen you should select “Obtain an IP address automatically” and “Obtain DNS server address automatically”. This will make your computer to ask your router which configurations it should use. Don’t forget to click on Ok if you needed to change anything on this screen.

Now that your computers are correctly configured, you should configure your router.