Strange network problem

Hello,
Ive just looked at 3 computers in a network and they seem to have a problem with one of them.
The main pc has shared folders on it but the other two computers cant connect to it. I cant ping the main pc from the other two but I can ping the other two pcs from the main pc.

Also the main pc has Nortons installed but no icon in the system tray and it didnt appear to be running. When I tried to install it I got an error message. I started to uninstall it but its taking ages. Im assuming this could all be virus related. What do you think?

I'm thinking Norton is screwed up and you are going to have to uninstall it manually.

What happens if you try safe mode with networking on the one computer that cannot be pinged?

Can it then be pinged? if so, NooNoo is right, Norton is mucked

Yes nortons was screwed up. Trend Micro found a virus and removed it and I used the Norton removal tool to get rid of it and everything worked fine. But then the silly customer insisted that I put Nortons back on because "Thats what weve always used."
Despite my attempts at trying to convince them otherwise.

Oh well they are a solictors firm and when I saw a price chart they had on their desk that said Hourly rate-$275 I figured they can afford to have someone come out once a fortnight or more to fix Norton stuff ups.
Some people have more money than brains...