Microsoft Internet Security and Acceleration Server 2000 Patch Packet Filter Log

From Microsoft:

To unconditionally block and log all outbound ICMP traffic that is sent from the internal network to the external network, follow these steps:

1. Apply this download on each ISA Server.
2. Then open the registry editor and go to the following key: /HKEY_LOCAL_MACHINE/System/CurrentControlSet/Services/MspFltEx
3. Add a registry key named "Parameters."
4. Add a value under the "Parameters" key, with the name "BlockOutboundICMP" and type DWORD.
5. Set "BlockOutboundICMP" value to any non-zero value.