I installed Norton 2003 pro on my computer, but like the firewall protection of Zone Alarm better, so I tried to install it. It worked, but as soon as my computer connected to the internet, it alarmed and ask me how I want to configure the fire-wall. I pick the radio box that said use this selection everytime, and click on allow. Immediately after that my computer restarted and did a XP disk scan, brought up the window user screen, and shut down again. Tried it 4 more times with the same result. Is there an known compatibility issue with Zone Alarm and Norton.