How to Enable Automatic IP in Windows 7
"Obtain an IP address automatically" is a default setting for windows 7, But if it has been changed by others, you may need to cancel these settings and make it to default.
1. Click Start > Control Panel > Network and Internet, open the Network and Sharing Center. Or you can right-click the network icon in the tray, select Open Network and Sharing Center.
2. Here it is Network and Sharing Center.
3. Click Local Area Connection in the screenshot above.
4. Click Properties in the Local Area Connection Status. If you want to assign a IPv4 address for your computer, please select Internet Protocol Version(TCP/IPv4). and click the Properties button, this is the most common selection.
5. In the Internet Protocol Version 4(TCP/IPv4) Properties
The settings in Use the following IP address is your windows current status, here we want to cancel the IP address, just choose Obtain an IP address automatically, and Press OK.
Usually we do not need to change the DNS server address, windows 7 or the ROUTER will get the default DNS server address automatically, next If you want to assign a special DNS server, just type them like this:
6. When you finished settings, click OK to take effect, you do not need to restart windows 7, If you find windows cannot obtain a new IP address from the connected router. Unplug network cable.