Weird connectivity issue

[jrsc109]

Hi all

I hope you can help.

I have 2 x PCs with Ubuntu 9.04 (Jaunty)
They are both connected to the router via wire (NOT wireless).

1 of the PCs connects to the internet without any issues.
The other can see the router, but will not connect to the internet. For whatever reason, I get a firefox error.

I am at a complete loss as to why this is.

The fact that I can see the router suggests that the network card is working (as it was, before I upgraded to 9.04). I can do all administrative functions on the router, including seeing the PC as an attached device.

So - why will it not connect further? There are no firewalls (apart from the default) on either the PC or the router.

I have 2 unhappy children, as they can't 'play'.

Please could someone offer some suggestions, advice and / or words of comfort.

Thanks

[Rubberman]

Check the contents of /etc/resolv.conf on both systems. My guess is that the one which is having problems has either an invalid or corrupted file.