XP network

[R'as al Ghul]

Isn't it enough to enable "Internet Connection Sharing" for the network connection that your desktop PC uses to connect to the Internet?
Have you tried that?

[Pannonian]

Isn't it enough to enable "Internet Connection Sharing" for the network connection that your desktop PC uses to connect to the Internet?
Have you tried that?

The network setup wizard did that automatically at the start, and I've checked it since.

On the desktop's internet connection's Advanced tab, I have all 3 options checked under Internet Connection Sharing, plus the Internet Connection Firewall.

On the desktop's LAN connection's TCP/IP tab, I have:
IP address: 192.168.0.1
Subnet mask: 255.255.255.0
Default gateway:

Preferred DNS server: a.a.a.a
Alternate DNS server: b.b.b.b

Where a and b are the DNS addresses used by the internet connection. I've resetted first the laptop, then the desktop, but the same error persists when I try to look outside on the laptop: DNS not found. File sharing works, but the laptop can't access the outside world.

[Blodrast]

I don't know much Windows stuff, but I have a couple of ideas. Currently, it's not clear to me what exactly the problem is. Yes, you can't connect, but why exactly ? Where does the chain break ?
So far, the advice you were given covers everything I would have thought of (and then some), so I don't know what else to add. But maybe we can figure out what exactly the problem is.

So, one thing to try is to ping from the laptop some host in the outside world; do this _without_ resolving names (dunno if this is default on XP, it is on the 2k box I'm typing this atm; if not, it should have a switch to tell it not to resolve names). If the ping works, then we've narrowed down the problem to some DNS issue; if it doesn't, we can stop trying to fix the DNS, since it's a lower level problem.

Another thing we could try is, like I said earlier, to figure out where exactly it stops. I'll assume that the firewall rules for allowing the laptop outside are correct (on all existing firewalls). If your firewalls allow you to do logging, please enable it, and see if something gets recorded when you try to access the outside world from the laptop. Do this with all the firewalls involved (laptop, desktop, modem if applicable).

If your firewalls do not allow logging, or not to a sufficient extent, what we can try is to use something like Ethereal (ethereal.com). Don't panic at the idea of "network analyzer", it's extremely intuitive and easy to setup and use. And it's free and multi-platform. You can set this up first on the desktop, and sniff packets from the laptop - preferably on the WAN interface, to see if the packets even make it all the way there. Hopefully, they don't, so we know that the problem is somewhere before that point. In either case, this will narrow down the possibilities and help us localize the problem.

If anybody else has other ideas, please feel free to correct me or suggest better approaches.

[Caius]

Help guys, and sorry for such hijacking of thread.

In home, we have 2 pc's. We both need Internet connection, but we have just one modem. The thing is, we need to share Internet, but we cant. a WMI error is ******* our red and it won't allow me to share Internet. I need help on what to do.

[caravel]

Caius, I'd advise you to start your own thread or this one is going to get very confusing.



/On topic: Pannonian

I'm not entirely sure what it causing the problem with this network. I think you should try what Blodrast has suggested but it may help to try and break it down a little and it may not but here goes.

The desktop PC (and USB Speedtouch Modem) are functioning as the NAT router/gateway (the windows ICS/Firewall service is exactly this). That is that this PC should have one NIC installed configured as 192.168.0.1 with the subnet of 255.255.255.0. The next step is to go into network connections and share the connection so that other Users can access it. If you don't do this then it won't be available. This PC can then be connected directly to an ethernet hub or with a crossover cable directly to another PC (or in your cace a laptop).

The Laptop needs to be set up as the next address along (or any other address in the same range 192.168.0.x) from the Desktop. So this is 192.168.0.2 with the same subnet mask. For this Laptop's Primary DNS server enter the address of the Dekstop (192.168.0.1). The final step is to go to Internet Options in the control panel and click on the connections tab. Select Never dial a connection or if this is greyed out, disregard. Then click on the LAN Settings button and uncheck all boxes and close.

Go to the console and do "ping totalwar.org". The output should show replies as below, if it isn't then a firewall on the laptop may be blocking it. Go to network connections on the laptop again and ensure that the Windows Firewall is not enabled on the LAN connection. If there is any other Firewall software running on the laptop, disable it, and test again.

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\>ping totalwar.org

Pinging totalwar.org [0.0.0.0] with 32 bytes of data:

Reply from 208.111.158.12: bytes=32 time=135ms TTL=49
Reply from 208.111.158.12: bytes=32 time=134ms TTL=49
Reply from 208.111.158.12: bytes=32 time=134ms TTL=49
Reply from 208.111.158.12: bytes=32 time=135ms TTL=49

Ping statistics for 208.111.158.12:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 134ms, Maximum = 135ms, Average = 134ms

C:\>