Additionally, a post from a guru suggests waiting until they issue a better installer.
Welcome to the Zone Labs User Forum
Zone Labs knows that some of our customers are having issues with the upgrade to ZoneAlarm 6.0, and is working hard to fix the situation.
The cause appears to be related to the upgrade process, not the application itself. Therefore, we recommend users experiencing difficulties uninstall any prior version of ZoneAlarm (v.2.x - v.5.x) residing on their computer system and do a clean installation of their new ZoneAlarm 6.0 product.
We sincerely apologize to any customers affected and appreciate your patience.