I am reviewing my secrity setup, and currently have (or could have) three firewalls - one on my router, the one on Windows 7 and the one that comes with Avast!. You will see that I have bought none of them specifically as a firewall - they are all spin-offs from other software or hardware.
So - is it better to have more than running, or could they clash? Is three better than one? Any thoughts?
Having a firewall in the router and another in the computer is a good thing. This is multiple levels of protection, always a good thing in security. But more than one firewall in the computer is bad and may cause unpredictable results.
Typically third party firewalls such as Avast will disable the Windows Firewall. As stated by another user earlier the multiple layers of protection is good however can result in issues when using applications which require sepcialised ports since these may need to be opened on all the firewalls in the network increasing the amount of the work needed.
Hope This Helps,
Josh! :)
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