You've just discovered a server that is currently active within the same network with the machine you recently compromised. You ping it but it did not respond. What could be the case?

ICMP is a core protocol within the TCP/IP suite defined in RFC 792, so this statement is factually incorrect - TCP/IP fully supports ICMP.

ARP operates at Layer 2 to resolve IP addresses to MAC addresses; if ARP were completely disabled, no Layer 3 communication including ICMP would work at all, but the scenario states you discovered the server is active, making total ARP failure unlikely as the specific cause.

ICMP echo requests can be explicitly disabled on a server through host-based firewall rules, OS-level settings, or network security policies - this is a common hardening practice. When ICMP is blocked, the server will silently drop all ping packets and return no response, making it appear unreachable even though it is active on the network. This is independent of whether TCP or other protocols are functioning normally.

On most modern operating systems the ping command can be executed by regular users without root or administrator privileges, so lack of elevated privileges is not the reason for no response.