Network Issue

[raf66]

Hi everyone. I consider myself a rather novice computer geek (and I use that term with the utmost respect I assure you) who is sooooo glad that I switched to a Mac a year and a half ago that you couldn't even begin to imagine. Well, I guess most in this forum could imagine since we likely are ALL very glad to have made the switch. Anyway, I am in need of some pretty serious help with a home networking issue.

My setup is this: iMac connected to the internet through a SpeedStream DSL modem that runs through a Belkin Enhanced Wireless Router. This allows my college daughter to connect wirelessly with her new MacBook Pro, it allows a Windows Vista wireless laptop (sorry but we've had it awhile) to connect wirelessly and it also allows a laser printer connected to this laptop to be used by the iMac and the MB Pro. We also have an XBox 360 and a PS3 to connect wirelessly. This basic network has worked pretty flawlessly for sometime (although we would all get logged out every now and then and we'd have to reboot everything) but it has now developed a pretty serious flaw: the iMac now has a message that appears constantly for the last week or so that says "another device on the network is using your computer's ip address (99.174.164.43). Please see the pic below. This is NOT an ip address that I've ever seen used by ANY machine on our network. Usually our addresses are the 192.168.*.* variety. Obviously this problem keeps everyone in my house from connecting to the network, and no amount of rebooting corrects the problem. The only way to reconnect is to run my DSL modem directly to my iMac and take the router out of the chain. While this works to get the iMac back online, no one else in the house can get online. The problem seems to have arisen without any change to the way we've always used the computers.

I am simply at a loss at a loss. Can someone help?

Thank you so much for your help.

 

[Hellhammer]

Have you tried reseting the router? BTW, reseting is NOT same as unplugging & replugging the power cord. There should be instructions on the manual. Updating its firmware may also help.

A temporary setup to get this work is to share the internet connection using iMac's built-in AirPort card. System Preferences > Sharing > Enable "Internet Sharing"

 

[nobunaga209]

^^I was thinking the same thing; sounds like you may need to reset everything rather than power cycle.

 

[raf66]

Thanks for the response HH and nobunaga. I'll try that. Also, I do have WEP security (with password) on the network so it would seem that no one outside my home is trying to login to my network. Would resetting this mess up my WEP security?

 

[Hellhammer]

Thanks for the response HH and nobunaga. I'll try that. Also, I do have WEP security (with password) on the network so it would seem that no one outside my home is trying to login to my network. Would resetting this mess up my WEP security?

Possibly but it's very easy to put back. Again, have a look at the manual. In my Dlink, it's two click procedure to make it password protected, I doubt it's much harder with Belkin

 

[assembled]

at a guess, you've plugged the modem into a LAN port instead of the WAN port of the Router, and the mac in the screenshot has picked up the external IP

recheck your cabling

the other alternative is that because you're not using a secure wireless network (WEP isn't secure), that somebody has got onto your network, and as you're still running WEP, I'm going to further guess that your router doesn't have a secure password on it and the person(s) that got onto your wireless network then got onto your router and changed its config.

 

[DoFoT9]

are you with sbcglobal?

if so, then that IP address you have provided us is your modems IP address - it has assigned your daughters laptop with its direct IP address - this is known as DMZ mode. i wasnt aware that DMZ could allow a number of computers to be connected through the same IP but maybe they can.

you will likely need to reset (and reconfigure) and modem and belkin router.