I've used Zone Alarm for years. I've never had any problems connecting to the internet using that program. Like with any firewall, it must be configured to allow programs to connect to the internet or it will block them.
The only problem I've had is with the latest upgrade. It wouldn't allow me to perform an error checking on any computer I have with it installed. Once I uninstalled the program, error checking worked fine. So, I reinstalled an older version of Zone Alarm and everything is working again without any problems.
My friend is having problems connecting to the internet through Road Runner cable which I also have two doors away. It is an on again off again problem. He contacted Dell (9 month old 2400) and they asked him what he had downloaded recently. He said that he went from the FREE version of Zone Alarm to the Paid verson. Dell told him to uninstall Zone Alarm as it was known to have problems. May I have your input on this please?