Win 7 networking problem - more than one NAT

I have a Windows 7 machine on a home network that is reporting the "More than one device is performing Network Addressing Translation" error. The home network is both wired and wireless. The router is a Linksys WRT54G connected to a Smart Stream 5100 DSL modem. Both have the latest firmware. The modem connects to an AT&T/Yahoo ISP.

There are two computers connected on wired connections and various laptops connect at various times over the wireless circuit. The Windows 7 machine cannot see the other machines on the network, nor can they see the Win7 machine but they can all see each other. Other than that, everything seems to work OK. I do not have a Home Group set up on the Win7 machine because none of the other computers are Win7. I use them for testing software on different OS’s and different versions of Microsoft Office.

When I first installed Win7 the machine connected to all the other machines just fine. I’m not sure what changed to cause this problem but right now I have to use a USB drive to move data form/to the Win7 machine and it’s a pain.

I have researched the problem on the internet but the only solution I saw that looked promising was to download 3rd party firmware for the router and go through a long, drawn out process to get the router into bridge mode which I didn’t fully understand. I’m not a network engineer but it doesn’t seem reasonable to need that level of knowledge to set up a home network. I’m leery of the 3rd party router firmware and haven’t found any way to determine exactly which devices are performing the NAT functions so I don’t really have a grasp of where the problem is other than there is more than one.

The Win7 and other machines are set up to be DHCP clients and the router is set up to be a DHCP server. The router and LAN machines are on 192.169.1.x and the modem is so they aren’t on the same network. The ISP assigns a DHCP address to the modem but since they aren’t on the same network I don’t see how that is causing the problem.

I tried a repair install but it didn’t change anything. I’m not averse to buying a new router but I’m not sure that will correct the problem. I don’t want to spend the money and then still have the same problem. Any help or advice will be greatly appreciated.
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  1. Are you certain that you SpeedStream 5100 does not have NAT enabled? Check your MANUAL how to login and check the settings on the modem. That's the only thing that makes sense as having a second NAT.
  2. RealBeast said:
    Are you certain that you SpeedStream 5100 does not have NAT enabled? Check your MANUAL how to login and check the settings on the modem. That's the only thing that makes sense as having a second NAT.

    That was the problem. I could not, however find anything in the modem manual or screens that referenced DHCP or NAT. It is buried deep. There is a setting in the Connection Configuration screen that says "Use private IP address". I had tried that earlier and had no internet connectivity.

    I found that selecting that requires reconfiguring the router to use a static IP address of because that address is fixed in the modem firmware when the "Use private IP address" option is selected.

    So the fix is to select that option. Then go into the router and select the Static IP address for the Internet Connection Type and enter the with a subnet mask of Then set the gateway to the modem's IP address which is and the ISP's DNS server addresses in the Static DNS fields. A little further down in the router page there is a section for setting up the router's DHCP server and it needs to be set to not assign an address of since that is now the address of the connection to the modem. I just started my DHCP addresses at

    There wasn't anything about this in the modem manual but I found another site that had info on the internals of the modem and that's where I found the address info.

    All the computers can now see each other which is what I was trying to correct but I still have a red X on the icon in system tray. Running the Win 7 trouble shooter sdidn't find anything though so I'm not sure about that. Do you have any idea how to locate the problem that is being indicated there?

    Thanks for your help. You confirmed my suspicions and got me to dig deeper. I know so little about networking I'm never really sure what I'm doing in that regard. Any help on the other problem would be appreciated also. Thanks again.
  3. That is a known issue in Windows networking that most people who figure out how to fix it seem to follow one of three approaches all related to an unknown incoming network connection: (1) if you use it on a network device turn off iCloud and see if it goes away (2) repair the icon following THIS Step by STEP, or (3) turn off extraneous services by cleaning your startup directory by using the guide under Start Up at EZ-LAN HERE.

    I've used the last two on different machines, but have never used iCloud so don't know if that actually works.
  4. Neither of those suggestions worked. I tried a couple of other fixes I found on the wbe and they didn't work either. It's really a nuisance more than a problem since I have connectivity to everything I need. I saw some suggestions that it may need to be resolved if I want to set up a VPN but since I don't need that I took the easy way out and just hid the icon in the system tray.

    Thank you so much for your help on the other issue.
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