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Networking issue

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My friend's laptop has decided to fall off the network and I have no idea what's wrong with it. It claims the cable isn't plugged in, but it is:


It was working fine, but for some reason, it required the network bridge to be disabled in order to work correctly. Every now and then for no particular reason, it decided to be a bit senile and re-enable the bridge, so it didn't connect anymore. Disabling it once again fixed the problem. So, in my not-so-infinite wisdom, I thought "Ah, if it doesn't need the bridge, I'll just delete it. That should fix the problem permanently". It would now seem I was quite mistaken.

I ran the network setup wizard, which put the bridge back, but I still can't quite get it back to how it was before I deleted the bridge and it still thinks the cable is unplugged when it isn't. Telling it to obtain an IP automatically doesn't work, nor does assigning one to it. Someone has already suggested that it might be a bad cable or port, but the timing coinciding with the deletion of the network bridge doesn't seem to support that theory. I'm sure I've cocked something up, but I have no idea what.

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Can you give us a few details about the network and what options you chose when running the network wizard? I'm just wondering about the need for a network bridge...

You've stated the broadcom is showing as disconnected, what about the other device in the bridge?

Edit: From your screenshot, I can see there is a Wireless adapter which is disabled. If that and your broadcom are bridged, this is why it isn't working. Same goes for the Hamachi adapter (which is only enabled when hamachi is running). But as AndrewB points out, its a rarity to need a bridge.

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Under any remotely normal computer setup, you should have absolutely no use for a bridge. Indeed, a bridge would mess things up.

Here is an example of where you might use a bridge:

Computer A ---- Computer B ---- Router

In this case, computer A would run an ethernet cable to computer B, and computer B would run an ethernet cable to the router. Computer B would essentially have 2 network adapters. You would bridge the two adapters on computer B, giving them both the same IP address. After performing a couple of other required steps, you would have the 2 computers and router connected in a chain formation, and they would operate exactly as if they were two computers connected to a router in a sane fashion.

If, for some bizarre reason you needed to do this instead of connecting both computer A and computer B to the router, then activating a bridge would prove useful. Obviously this configuration requires computer B to always be on in order to allow data to pass from computer A to the router. Be aware, also, that Windows XP has a buggy implementation of bridging. If the computer with the bridge goes into standby or hibernate mode, the bridge will stop working, even after the computer comes out of those modes. In that case, you would have to manually remove and recreate the bridge.

Interesting lesson aside, it sounds like you need to find a way to ditch this "Network Bridge."

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A disabled bridge, everything works, a deleted bridge nothing works. And a message about an unplugged cable which is plugged in.
As long as your friend doesn't have internet he doesn't need a firewall so please stop that service. (I just want to be sure that the internet connection sharing service isn't running)
Anyway a sanity check from the command line:

netsh bridge show adapter 
netsh bridge show mode
The first line will give back the two network cards, the second line offline. Delete the bridge (like you did be4) and now netsh bridge will return an empty line. (otherwise:wcs, I'm afraid)
netsh dump > c:\doomworld.txt
This will dump your network configuration so we can see it here and if you do please post also the model of your friends router.
That message about an unplugged cable indicates a problem related to the bridge,the interface of the network card, cable, router interface.
Assuming you had a cable connected to the router, deleting the bridge shouldn't make a difference. So you did nothing wrong. I don't think the cable or the interface of the router matters here, cause there's a direct link between deleting the bridge and loss of connection.
it's all about resetting that network card. But since rebooting doesn't work, removing the driver,reboot and reinstall might do it.
Or maybe disable the network adapter, enabling another one, rebooting and reverse, who knows that reset it.
Please note that the wizards will create a new bridge in their default configuration. There's an alternative for wizards and gui's you might know now
netsh interface ip set address "n" source=dhcp
where "n" is the one in Network connections on the left like "Local area connection". You can change that with right mouse.
If you know the ip addresses of your friends router and pc then you can try static too
netsh interface ip set address "n" static 1 
The previous setup is quite often used by soho routers. (and doesn't leave a trace compared to dhcp in some). Hope this helps.

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