Every one is so great on this site I hope you can help. Here goes:I have 4 computers on my wireless home network. Two laptops (Windows 7 & Mac OS 10) with internal wireless cards and two PCs (Windows XP) with Linksys wireless adapters. I use an Apple Airport Extreme (Model A1254) wireless access point.Three weeks ago, when Comcast Cable transitioned to all digital (I have my internet through them as well), I immediately lost internet access and wireless communication on all computers, printers and VOIP Phones.Because I was receiving a 169.xxx.x.x IP address on my main computer, I was instructed to and replaced my modem with a 1000BaseT model , replaced all ethernet cables with Cat6, and replaced the network card on my main PC with a D-Link 10/100/1000 mbps. Still no internet.The guys at Apple could not figure our why I could not connect so one changed my DNS server to a public one and all computers, except my main computer, immediately connected. They are now configured to obtain automatically and they are still connecting.When the Apple guys connected my ethernet cable from my main computer to the Airport Extreme, it would not connect and I received a 169 IP address and no DNS server address. When they connected my ethernet from my Airport to the other working laptops, they connected without problems and receive a valid IP addresses.They felt that some how the Comcast transition might have changed something with my networking/internet settings on my PC using Windows XP SP3 since my settings had been basically the same for 2 years. I have McAfee and Windows Firewall that I disable when I am trying to connect,When I look under connectivity in Systems Information, I have 0.0.0.0 for my IP address, subnet mask and dns serversDoes anyone have any suggestions? Thanks in advance.1 person needs an answerI do too

HiDid the change in the Comcast's service was accompaniied by changing Hardware.When using such Multi service, the ISP usually provides a Modem Router.If a new Router was instlled it might be that the IP address scheme is Not compatible with your Network and thus there is No connection.What Comcast support is saying about this problem? Jack-MVP Windows Networking. WWW.EZLAN.NET

When the problem first occured, I was using a Motorola Surfboard Modem, Model SB5100 and had used it many years with no problems. Comcast's techs said that the new problem had to be with the modem so I rented a modem from Comcast, a Ubee D3.0. When that did not solve the problem, they said it had to be with my ethernet cables, even though I was already using fairly new CAT 5E cables. So I replaced them all with CAT 6 but no change. Then it had to be with my internal network card which with was a 10/100 mbps card. I replaced it with a 10/100/1000 card. No change. Now, they are saying that is has to be a software issue, what ever that means.I had an appointment for a tech to come to my home today but no one ever showed up. I have tried everything I can think of to solve this problem.Last evening, I unscrewed my modem from the cable cord, unplugged it and disconnected the ethernet cable and waited 30 seconds and restarted my computer. At first, nothing happened so I called Comcast's automated self-help line and requested a signal refresh to the modem. After about two refresh signals, all of my computers connected to the internet, wirelessly and wired for my main computer. This was the first time that my main computer connected since June 27, 2010. But after about 4 hours, my main computer suddenly stopped connecting and has not reconnected since. My other three computers are still wirelessly connected and showing no problems.My VoIP phone, that is connected directly into my airport, is working fine as well.Go figure!!!