How come I get conflicting IP addresses on my local network?

by on October 31, 2010

Q: Is it possible to see the sites from another computer on your local network after having an IP conflict?

Here’s what happened…

I opened my browser today and was told that I had an IP conflict with another computer on the network. I’m deployed and share a LAN with about 13 other guys on the same router. I closed the warning, released the IP address (forgot to renew it, however) and went about my business. Later that day, I opened facebook and I was logged into the page of another guy who is here on this same LAN.

This isn’t the first time this has happened; I was once approached by a guy here, who knows nothing about computers, who asked me if I’d been in his room on his computer, because I was logged into facebook on his as well. I really didn’t believe him, but I guess this proves it.

I’ll add that I know my releasing the IP and forgetting to renew it isn’t the cause, because of the time this happened in the past. Also, my job here is that of “computer guy,” so it’s my responsibility to figure this out. Any help would be greatly appreciated.

One Response to “How come I get conflicting IP addresses on my local network?”
    Picked as best answer

    First, make sure all the computers are using DHCP to assign IP addresses, make sure DHCP is turned on with the router.

    The router will assign IP address to the computers, and probably keep them pretty much the same. Take a close look at how IP addresses are getting assigned on your network and you should be able to track down the problem.