XP network problem; firewall question

[gbe]

I have a LAN consisting of two PCs and a hub. Since upgrading one PC
to XP SP2, neither PC can ping the other. I gather from reading here
that the problem is often with the XP firewall. I think I have this
turned off, but you never know.

Using Ethereal packet sniffer, the other PC is sending ARP "who has <ip
address>?" packets, which the XP responds to. Would the firewall
interfere with ARP packets?

When pinging, the XP also sends ARP "who has <ip address>?", which the
other PC also responds to. But, the XP is apparently unhappy with this
response, since it just repeats the "who has ...". Could this indicate
a firewall problem?

Thanks,
George

 

[gbe]

Just for completeness: the problem was that, in XP, someone (me?) had
set <connections - LAN - properties - adapter - config - advanced -
network address> to the (valid) IP address. After changing this
setting to "none", I can now ping.