Back in the good old days when I was on dial-up, I tried using Zone Alarm and in the end I gave up and used Tiny Personal Firewall.
Zone Alarm caused me nothing but grief - it was either always popping up and asking about this that or the other, or it would refuse access to some things that had been working perfectly well up to that point. Somewhere I seem to remember reading that Zone Alarm had built-in spyware. Whether that's true or not remains to be seen.
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