Note: This post applies to Windows 7.
By default the Windows Firewall will block any ping requests made to the host. To enable a ping response we need to add a rule to the firewall. First go to Control Panel –> Windows Firewall. On the left hand side select Advanced Settings.
Select the Inbound Rules. Sort the rules by name and find File and Printer Sharing (Echo Request – ICMPv4-In). There’s typically 3 versions of this rule, one for each “network” defined in Windows. Enable this rule for the required networks.
Just some background – ping requests work using a special network protocol called ICMP. ICMP is a network management protocol and an Echo Request is a type of packet set via ICMP used to determine if a host is up or down (and indicate the response time). Often these ping requests are discarded in order to tighten security. One of the first thing potential hackers may do is ping an IP address to determine if the machine is “on” before trying anything further.