Networking → [Connection Sharing] Unable to Ping Self

I'm trying to add a new laptop (HP DV1580se) to my home network with Linksys WRT54G and Sprint DSL. Configuration seems to be good and the new laptop will access the internet just fine, but it will not recognize my lan resources (computer, disks, printers) and is not accessible from the other computers. Fundamental to this is that I cannot ping this laptop from itself or from the other hosts. Ping 127.0.0.1 works and I can ping other computers including my router and internet gateway. IPConfig gives valid addresses and Workgroup. Nothing appears in XP's Network Places, but the new machine does appear in the other system's Network Places.

Main question: Why can't the machine self-ping?

Do you have any kind of software firewall installed on your laptop? I'm guessing you ran network setup wizard on YOUR laptop. Try doing a tracert from your computer to your laptop. SATASI

Yes, I did run the Network Setup Wizard both on my existing systems (which didn't change anything) and the new laptop. No problems reported.

A tracert from my machine to new laptop times out. Tracert from the new laptop to my machine works just fine.

Additional info: When trying to View Workgroup Computers on the new laptop, it times out and pops the message " is not accessible. You might not have permissions to use this network resource. Contact the administrato.... The list of servers for this workgroup is not currently available." Mostly spurious, but I the accessibility is the issue.

BTW, disabling the ICF does not change this situation.

Do a ipconfig from both computers and post here so we can look at it. SATASI

The IPCONFIG output from both machines is identical except for the workstation id.

Do you have any idea why a computer would not be able to self-ping when all other components of TCPIP seem to be running properly?

What exactly do you mean by workstation id? The hostname? IP address? I don't see an item called workstation id in my ipconfig /all output.

You probably have another personal firewall, that you don't realise. That happens, fairly often too.
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Could be LSP / Winsock corruption too.
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Give us a chance to help you. Post "browstat status" and "ipconfig /all" from each computer, don't just examine ipconfig yourself ("output from both machines is identical"), let us diagnose the problem. Read this article, and linked articles, and follow instructions precisely (download browstat!):
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