You might find that your Windows computer does not respond to ping from another computer on the same network. You can ping from it, but it does not respond to ping.
The most likely cause of this is that Windows Firewall is turned on. And by default, it disables ICMP echo request in its inbound rules. Enabling ping is easy:
Go to Inbound Rules and enable Networking - Echo Request (ICMPv4-In) for the network profile that is being used.
You should be able to ping this computer as soon as this is enabled.
Tried with: Windows 7 x64