[Modified Thursday, Jul 5th 2012 by claude]
For Windows 7:
• As administrator,
• Click on the Start icon,
• Select Control Panel,
• Choose Network and Sharing Center,
• Open Local Area Connection,
• Select Properties,
• Double click on Internet Protocol Version 4 (TCP/IPv4).
Configure as follows:
Check "Obtain an IP address automatically" and "Obtain DNS server address automatically".
If you are still having problems getting rid of the old IP address, from the Start menu, select Run... -> type in cmd -> click OK --> then at the command prompt, type in the following:
ipconfig /release [enter]
ipconfig /renew [enter]