If you see alerts from non-routable IP addresses, this is most likely from a machine on your local network, or your NAT (hardware) router if you have one. Private IP addresses are non-routable - this means that they exist only on your local network and cannot normally be routed to or from the Internet.
The private, or non-routable, IP addresses are as follows (x can be any legitimate IP number):
- 172.16.x.x through 172.31.x.x
When you see these alerts, determine whether it is from a computer on your network, or from the machine or router that performs NAT or DHCP (most commonly, if the IP address ends in 1 then it would be the device performing NAT/DHCP).
The most common cause of these alerts is not having the Trusted Zone set up properly. Be sure that your local network systems (and router as necessary) are included in the Trusted Zone (set to Medium). Also, you may need to UNcheck the box to block local servers.
If you wish to not see certain types of alerts.
To suppress alerts - Open ZoneAlarm, Click on the Tools dropdown, Select Logs.
Then click on the Alert Events tab. Then select/deselect the alert types that you do or do not want to see/logged.