Can't Ping The Girl's Laptop

On my home network, I have a Linksys WRT54G router running DD-WRT firmware. It is using DHCP but is set to provide static leases. My laptop gets 192.168.1.111 and The Girl's laptop gets 192.168.1.121. IPConfig /all confirms for both computers that those are their IP addresses. Both our computers are connected to the network. We are both in the same Workgroup on the network. Both laptops are running Windows 7. I can navigate her public folders from my computer in Windows Explorer. But when I ping her IP address, I get request time outs. From her computer, I get the same time outs when I ping my laptop's IP address. From both computers, I can successfully ping other devices on our network. On the router System Information GUI in my browser, I do not see her computer among the DHCP Clients List. However I do see her MAC address in the LAN section of that GUI. What might be keeping us from successfully pinging each other?

What malware and firewall are you using? Ping uses a different port than sharing or browsers.

I use Comodo firewall and anti-virus as well as MS Security Essentials. The Girl does as well.

jealousmonk said:

I use Comodo firewall and anti-virus as well as MS Security Essentials. The Girl does as well.

Have you tried disabling them to see if they are responsible?

Have you tried ping in safe mode w/ networking? (F8)