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Imagine what would happen if two homes in a certain city had the exact same address. The two families living at the houses have no relation to one another, but their house numbers, street names, and zip codes are completely identical. There’s no apartment or suite number; they’re both just “123 Green Grass Blvd” in Anywhere, Texas. Chances are, the residents of the two houses would frequently get each other’s mail, and visitors trying to find one of the families would often wind up in the wrong place.

This would probably never happen in real life—the municipal government simply wouldn’t allow two houses to have identical addresses. But curiously enough, when your computer alerts you to the presence of an IP Address Conflict, it’s trying to tell you that a very similar situation is unfolding in your machine’s wireless network.

IP & DHCP
Before we can talk about IP address conflicts, it’s necessary to have a basic understanding of what IP Addresses actually are. An Internet Protocol Address is a specific “code” that corresponds to a single web-enabled device on a network. The address is made up of four different numbers, each one ranging from 0 to 255 and separated from the others with a period. For example, one computer’s IP address could be 12.245.6.111, another could be 86.108.72.30, etc. IP addresses are important because they’re essentially how information on the Internet or network knows where to “find” your computer. When you tell your browser to download something (webpages, email, files, etc.), your IP address is what guides the content to your specific machine.

Most IP addresses are dynamic, which means that they change from time to time—your computer/tablet/device doesn’t have its own number so much as a number is “leased” to it every time you want to use a network. IP addresses are usually leased for a period of seven days, and while they’re often renewed automatically (so a computer could, in theory, have the same dynamic IP address for years), they do sometimes expire.

This is where a Dynamic Host Configuration Protocol, or DHCP, comes in. The DHCP that your network uses is usually managed by your Internet service provider, and it has a “bank” of IP addresses that are available for it to give to people. When someone goes online and needs a new IP address, the DHCP assigns their computer the next available one that it has. In most cases, this whole process happens in a fraction of a second and the computer’s user doesn’t even notice it. However, the process is not 100% foolproof.

Double-Dipping
When your computer notifies you of an IP address conflict, it is telling you that another device on the network already has the exact same IP address that it wants to use. In this case, your computer will refuse to log on to the Internet (or interact with any other devices in the network), because doing so would cause confusion about where you and your “twin’s” data and downloads are supposed to go.

There are a few situations that might lead to an IP address conflict:

  • One computer (“Computer A”) is put into sleep mode, so the DHCP assumes that it is done using its current IP address. Meanwhile, another computer (“Computer B”) needs a new IP address, so the DHCP assigns it the number that was previously used by Computer A. When Computer A’s owner wakes it up and tries to launch their browser, Computer A tries to use the same IP address that it did before, not realizing that it was reassigned to Computer B.
  • Some computers on the server are using dynamic IP addresses and others are using static (that is, unchanging) IP addresses. The DHCP grabs one of the IP addresses it has at its disposal, not realizing that it’s just assigned a dynamic IP address that is identical to a static IP already in use.
  • Human error has led to two computers being assigned the same static IP address by a system administrator.
  • A software error has allowed two computers to be assigned the same IP address by the internet service provider.
  • The DHCP is malfunctioning and not handing out dynamic IP addresses the way it should.

How to Deal
Now, fortunately, IP address conflicts usually are not that big of a deal. Here are some tips that might help you fix the problem at home:

  • Wait it out. Because most home computers and devices have dynamic IP addresses, eventually, your computer will automatically receive another one from your DHCP. Chances are, the DHCP will issue one that’s currently not in use, which will resolve the conflict.
  • Restart your computer or manually release your current IP address. The simple act of restarting your computer will generally force the machine to speak to the DHCP about receiving a new IP address instead of trying to use the one that it thinks is currently leased to it. If you don’t want to reboot your computer for one reason or another, you can also open up the command prompt, type in either “ipconfig /release” or “ipconfig /renew,” and hit ‘enter.’ This command essentially tells the computer that you want to acquire a new IP address.
  • Restart your router. Doing a hard reboot of your router will also force your computer to speak to the DHCP about receiving a new IP address.

If none of these steps work, the problem may lie with your wireless router itself or internet service provider. In either case, you’ll probably need to consult with a professional to diagnose and resolve the problem.

Conclusion
A notification of an IP address conflict may be perplexing, but it’s usually just a “hiccup” on the part of your computer, router, or Internet service provider instead of a sign that something is seriously wrong. The old suggestion of “Have you tried turning it off and turning it back on again?” may be a cliché, but this is one situation in which it could actually be the proper course of action.

If nothing you’ve tried at home has resolved the issue, or your computer is constantly experiencing IP address errors, it’s probably time to have a professional investigate the matter. In that case, give us a call at 817-756-2241. Regardless of where the problem lies, our repair services can help get you—and your browser—back up and running!