When I have connected my routers defined in GNS3 with a cloud pointing to my network card . HQ was able to access my LAN because it shares the same LAN .But in my Frame-Relay WAN , even if  I have all the networks in my routing table , it is impossible for a Branch location to ping something on the real network where you have Windows 7 or Windows Vista machines.

So after some reseach, I have found this interesting note: http://www.howtogeek.com/howto/windows-vista/allow-pings-icmp-echo-request-through-your-windows-vista-firewall/

Even if it is related to Windows Vista and even if you have some warning , it is applying this little patch. When , you apply under the DOS prompt the following command : netsh firewall set icmpsetting 8 enable . It will create depending on your topology  a new rule inside the Firewall “Networking – Echo Request(ICMPv4)”. This rule will be enabled.

In case if you want to revert your manipulation , as the command to revert back present in the previous document is not working , go then top the control center and find the previous created rule or rules and disabled it …

With this patch , you can enable your Windows 7 to icmp request.