Due to the potential for conflicts and problems that can arise from using
multiple firewalls, ZoneAlarm recommends the use of only ZoneAlarm and
a virus scanner.
When multiple software firewalls are installed, there is no way of ordering
which product will get a packet and which will report it; the determination as
to which product gets operating system preference to monitor the traffic will
be made at random. When running more than one firewall, ZoneAlarm
might not be able to report on incoming port scans or hack attempts. In
some cases, running two software firewalls at the same time can cause
more problems than running only one.
ZoneAlarm works well with hardware firewalls - in these cases the hardware firewall would protect incoming ONLY (you would need to set that up for logging if you wish to see those alerts) while ZoneAlarm continues to protect with Outbound Control. Also, note that some software firewalls, such as the built-in Windows XP firewall) provide inbound protection only.
ZoneAlarm provides both inbound protection and outbound anti-Trojan
protection via application control.
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responsible for, the content users may find on such sites.
If you need assistance with any ZoneAlarm product, please contact a Customer Service agent using our Live Chat option below: