The system has detected an IP address conflict with another system

The system has detected an IP address conflict with another system

• Ever get the following message when turning on your computer or taking it out of sleep mode?
• There is an IP address conflict with another system on the network.
• You may also see a different error message for the same problem.
• This IP address is already in use on the network. Please reconfigure a different IP address.
• This occurs when two computers on the same LAN network end up with the same IP address. When this occurs, both computers end up not being able to connect to network resources or perform other network operations.

This problem, though rare, can occur because of the following reasons:

• Two computers are assigned the same static IP addresses.
• One computer is assigned a static IP address that falls into the DHCP range for the local network and the same address is assigned to a computer by the DHCP server.
• A laptop is put into sleep mode and then turned on while connected to another network that uses the same IP address.
• If you have multiple network adapters, it is possible to have an IP address conflict with itself.

How to resolve an IP address conflict

There are a few ways you can go about fixing this problem. I’ll start with the simplest and move on.

1. Reconfigure Static IP Address – If your computer is using a static IP address, it is best to try and use a different one in the same subnet. One way to check to make sure the one you are picking is not already being used is to simple ping the IP address (ping x.x.x.x).

• We will change the IP address and DNS servers using the built-in utility in Windows called “Netsh” is a nifty utility to change system networking settings, locally or remotely. To run Netsh click on start then RUN and type CMD press ENTER.
• When the command prompt comes up type Netsh, now you should be ready to execute commands. Simple huh. Just to warm up type “interface IP show config“ that will show up the TCP/IP network settings.
• Now, how you change the IP address and Default Gateway settings? To change the Local Area Connection TCP/IP settings type the following command:

interface IP set address name=”Local Area Connection” static 192.168.10.42 255.255.255.0 192.168.1.1

• As you can see, when you use Netsh you need to specify what network properties you need to change, in the example above, we changed the network properties for “Local Area Connection” then we setup a static IP address, Subnet Mask and at the end the default gateway.
• Changing the DNS IP address is almost identical as the procedure above, type the following command on the Netsh prompt:
• Interface IP set dns “Local Area Connection” static 192.168.1.1
• To Setup WINS, type the following command:
• Interface IP set wins “Local Area Connection” static 192.168.1.1
• To set the network properties to obtain the IP address from a DHCP server, type the following command:
• Interface IP set address “Local Area Connection” dhcp
• To set DNS to obtain IP address automatically type the following:
• netsh interface IP set dns “Local Area Connection” dhcp
• There you have it, a useful tool to help you on your network configuration.

2. Use DHCP – If you don’t need to use a static IP address, it’s best to simply choose DHCP instead of manually configuring the IP address. The server will know which addresses are free and which are taken.

3. Update firmware – In some rare instances, the actual DHCP server can malfunction and assign more than one computer the same IP. In this case, it is best to try and update the firmware on your router.

If you’re still having an IP address conflict, post your problem here and I’ll try to help you out! Enjoy!