Home network (LAN) problems

[Xplorer]

Hello!

I have two PC's at home, both running Windows XP SP2. PC1 has a built-in LAN
into to mobo, PC2 has a PCI lan card. Both have external 56K modems. When I
set up the network, I configured PC1 to connect to the internet, and PC2 to
use the PC1 internet connection. I had no problems initially with the setup.
However lately, I get a yellow triangle with the exclamation on either
machine telling me limited or no connectivity. Did it have something to do
with the PC2 connecting to the internet at one time when PC1 was turned off?
Everytime I try to "repair" the LAN setup, I end up with the same message.
Now even PC1's LAN setup cannot be repaired. Both can still share files and
printing, but PC2 cannot connect to the internet using PC1.
I tried reversing the configuration with PC2 connecting to the internet with
PC1 connecting through PC2. The setup worked! But I want the original config
because I have PC1 on at all times and PC2 turned off at times. Any
suggestions or help please?

Is there a way of erasing all the configurations in the PC's registries and
hard disk so that I could start from scratch? If so, how do I do it? I tried
uninstalling and disconnecting the LAN and LAN card, and then reinstalling,
but the setup would pick up the old configuration settings.

Is there a software utility that helps set-up home networking and diagnose
and help solve problems other than the troubleshooter that comes with XP?

Thanks to everybody!

Xplorer

 

[Hans-Georg Michna]

However lately, I get a yellow triangle with the exclamation on either
machine telling me limited or no connectivity.

Probably a hardware error. Swap the cable. If that's not it, you
may have to swap the Ethernet adapters.

Hans-Georg