How to Renew an IP Address in Windows 7
When connecting your new computer to an existing modem, you won't have an immediate Internet connection because the IP address will need to be renewed. In some instances, the IP address will automatically renew if you unplug the modem and restart your computer. However, in most cases you'll need to release and renew the IP address.
Connect your computer to the modem. Do not unplug your modem yet. Start your computer and navigate to the desktop.
Open the "Control Panel by navigating to the "Start" menu and clicking "Control Panel." Select "Network and Internet" and "Network and Sharing Center." The Network and Sharing Center dialog appears.
Click "Change adapter settings," found in the top-left of the dialog. A "Local Area Connection" icon appears. Right-click on the "Local Area Connection" icon and select "Disable." This disables the Local Area Connection and also releases the IP address. Below the LAN icon, the word "Disabled" appears.
Unplug your modem. If the indicator lights are still lit after unplugging your modem, then you'll need to remove its battery. All the indicator lights on your modem should be off because this indicates that the modem has completed the releasing of the IP address.
Plug your modem back in after 10 to 20 seconds and allow the modem to fully reset, which usually takes a minute. The flashing of the indicator lights indicates that the modem has completely reset.
Right-click the "Local Area Connection" icon and select "Enable." This will complete the process of renewing your IP address and restoring your Internet connection.