I found this suggestion on Zone Alarm forum and applied they work! So I post them to help other people on this newsgroup Best regards Roberto (IW1ERL)
ICS Settings: .................................................................................................. On the gateway machine, do the following. Click start -> run, type cmd and click ok. Type ipconfig /all and press enter. Find the connection you are using, and make note of all the DNS servers. Type exit and press enter.
Double-click the ZA icon down by the clock. Click firewall -> main, and click the advanced button. Put the check in "this computer is an ICS/NAT gateway" , and click ok. Click firewall -> zones.
Add each DNS server to the trusted zone. To do this, do the following. Click the add button, and then click IP address. Click trusted, put in the IP address, enter a description, and click ok. When finished adding all addresses, click the apply button.
Next, click program control -> programs. Locate Generic Host Processing. Under the server column, for trusted, change that to a check. Don't change server internet to a check, just server trusted.
If you have ZoneAlarm on the other computers, do the following. Click the ZA icon down by the clock. Click firewall -> main, and click the advanced button. Put the check in "this computer is a client of an ICS/NAT gateway" , and click ok.
Bill