Can't create hurricane electrics tunnel. IP is not ICMP pingable. Please make sure ICMP is not blocked. If you are blocking ICMP, please allow 66.220.2.74 through your firewall.

Hi everyone, so I've been trying to create a tunnel on Hurricane Electrics, but I constantly get the error which is the title of this post. So this is part of a school project but our proffessor didn't say much after I've showed him the error,but to disable firewall, which I did. I disabled my router firewall, I created a new rule for ICMP allowing it to go through the firewall on my pc, but yet i keep getting the same error. I've tried vpn or proxy thinking it would fix it but no luck there either... So I get that port mapping or DMZ could help me but don't really know how to use them or set them up so that it would work, so if anyone can help me please do.