DHCP in Windows 7

Source
So your router supports DHCP and you want to know how to enable DHCP in Windows 7? DHCP is actually enabled by default, because all modern routers nowadays support DHCP, but if your configuration is messed up somehow, you still might want to check it.

Network Properties
1. Right-click on the “Network” icon on your desktop and click on “Properties”:

Local Area Connection
2. On the following screen you will get basic network information and see all of your current connections. One of the connections, should be called “Home network” (if you did not set it to something else, e.g. Work network).

Click on “Local Area Connection”.
Connection Status
3. The status screen of your “Local Area Connection” will appear. Click on “Properties”:

LAN Properties
4. Click “Ok” when prompted. Scroll down the list until you find the entry “Internet Protocol Version 4″ and double-click on it. (as you can see the Internet Protocol 6 is currently unchecked, more about that later).

Internet Protocol 4 Properties
5. Next, you will find the settings that allow you to enable DHCP for your connection or disable it and retrieve a static IP. In this case I entered a fictive static IP:

We have the following entries that are important.
a) Obtain an IP address automatically
b) IP Address
c) Subnet mask
d) Default gateway
e) Obtain DNS server address automatically
f) “Use the following DNS server addresses”
g) Preferred DNS server
To enable DHCP, you have to make sure to check the options a) and e). That’s how you tell your router to automatically find the addresses provided by the DHCP. DHCP stands for Dynamic Host Configuration Protocol and is basically a protocol to retrieve IP addresses automatically and that’s exactly what we want to do, right?
Disable DHCP
If you want to disable DHCP instead of enabling it, you can enter a static IP. In your router manual, you will find the default IP gateway. Write it down or remember it. Then enter the IP into the field d) and g). Copy the gateway address from your manual again and enter it into the field IP address, but the last field should be a random number other than the default gateway IP.
Example:
You router gateway IP could be:192.168.5.1
Then you enter the IP address:192.168.5.xxx (every other number other than the one defined by your router, in this case “1″)
How to disable IPv6
As you might have noticed, I disabled IPv6. New broadband routers support IPv6, so you can also follow the instructions above and simply use Internet Protocol Version 6. Keep in mind that IPv6 are longer.
If you want to find out if it’s a good reason to enable IPv6 or if you should disable it, you can read this guide:
Disable IPv6 in Windows 7?