Hello,
I'm just trying to install for the first time a small Linux server. I've installed Mandriva. The installation went fine, but now I have some networking problems. My network consists of the Linux server and two WinXP desktops. All the machines are connected to a router that is connected to a cable modem. All machines can access the Internet, the linux can ping the router and both WinXPs, but the workstations can ping only one another and the router. When I ping the server I get "request time out". That is the server can ping the workstations, but the workstations cannot ping the server. I guessed that it might be the firewall, so I figured out that I should stop iptables and shorewall services. I stopped them but it seems to change nothing.
What's going on? Please help me.

Just to make sure the iptables is flushed use the command as root.
/sbin/iptables -F

Now try pinging. If it works then some firewall settings are still active,

Brian1

Ran the command. Now I can ping nobody even not localhost Should it be that way?

server must be blocking ICMP , try the command

iptables -L

and post the output

If the XP machine has Service Pack 2 installed, then the Windows firewall will be enabled by default. Go into Control Panel and open up the Firewall settings, then disable it.

That should fix it