Windows 7: ics not broadcasting dhcp to router wan port

Greeting, I'm having problems setting up a ICS route in win 7 the same procedure worked fine in XP.

I have a dual boot win xp pro, win 7 pro x64 system.

The internet chain consists of a 3g modem (ics) <-> gigbit nic ip (192.168.0.1 in XP) (192.168.137.1 in Windows 7 pro)<-> wan port of a dd-wrt v2.2 firmware linksys54g.



There is a second gigbit nic linked to a switch.

I used this arrangement on XP for quite some time with no issues. Laptops could connect wirelessly through the router to the internet. ICS in XP would assign an IP to the router wan port in the the 192.168.0.xxx range.

In Win 7 this doesn't work the wan port is assigned 0.0.0.0 by ICS.

Booting back into XP and it works fine. This leads me to believe either the ICS dhcp isn't assigning an IP or something in Win 7 is blocking it. I've tried more things than I want to mention. Anyone have any ideas as to what is wrong?

Thanks DArt

Perhaps IPv6 in win 7, or firewall AV. If you are using homegroup and IPv6 in win 7, create a new network connection using workgroup (uses ipv4)


Ken J

I disabled homegroup completely and IPv6 for that nic, no difference.

OK maybe take a different tack. What changed in ICS (other than than the default ip range) between WinXP sp2 and Windows 7.?

I havn't tried this myself but this has been working for ICS. I believe that bridging the connection is the key to getting DHCP to work.

Here's a checklist of things for ICS and file sharing for 2 croslinked computers (in my case a Windows 7 and XP one):

- both computers set to the same workgroup
- restarts
- advanced sharing settings - all things turned on (network discovery etc.) except for password protected sharing
- bridged the connection with the internet
- turned on Internet Connection Sharing for the internet connection - this forced an ip to the other connection (192.168.137.1) and gave an option to select which connection should have access to the ICS (the second connection or the bridge - you choose the second / crosslinked cable connection)
- shared some folders on both computers
- worked instantly (the other pc aquired a correct ip and internet)

From this thread.
Internet Connection Sharing between 7 and XP

But I have to ask, if you already have a router why not just use a switch to connect your other machine? I certainly wouldn't use ICS if I already had a router.

I'm using a 3G modem as my internet connection (downside to rural living). I could buy a USB capable wireless router ie. Nexaira or Cradlepoint but haven't had to for my usage patterns. The 3g modem is a dial-up connection and I show no option to bridge it to any other connection. My only option has been to use ics to connect from the dialup - lan adapter - router then broadcast throughout the router wireless range to allow connections to my laptops. This method worked fine for years using XP Pro.

Connecting through the WAN on the router allowed me to have an internal network with an external internet connection that was routed through the router firewall.

I'm not sure about 3G but it seems like you should have it set up as 3G modem>WRT54G router> other pc's connect to roters wireless and eithernet switch to more pc's.

This would give you DHCP for everything after the router and using the same default gateway for sharing to work.

Although I'm not sure about the limitations of 3G because I havn't messed with it.

This 3G modem is usb you can't connect it to most routers, the ones I mentioned being exceptions. The router needs a usb port and the firmware to allow the specific modem. I'd give up and buy a new router but it worked fine in XP and I can't imagine why I can't get it to work in Windows 7.

hmm I changed it to automatic metric on the NIC and it assigned a dhcp to the wan ip now to see if I can get internet, Yeah progress

I still haven't managed to get ICS to transfer between internet and laptop. I have been able to reproduce how I got the router to pick up the ICS dhcp IP.
1. I unplugged the router wan port
2. Set ICS between the dialup and the NIC that connects to the router wan port.
3. plugged the wan port back in.

edit:
From reading around it appears between Win XP and vista/7 something was broken with ICS. There are some serious problems with passing dialup data packets through an ICS connection.