How do firewalls prevent viruses?

If you use a computer at home, the most effective and important first step you can take to help protect your computer is to turn on a firewall.

A firewall is a software program or piece of hardware that helps screen out hackers, viruses, and worms that try to reach your computer over the internet. In that sense it acts more as a filter than a wall, screening out threatening communications.

Firewalls function using a system of either inclusive or exclusive parameters, allowing specific types of communication in and excluding others.

Generally, a firewall is controlled by an access control list, which has a particular set of guidelines that allow or resist access to specific computer communications.

Most computers have a firewall built-in and turned on by default, but that is just a good starting point and you should build your defences from there.

You should have a hardware firewall (such as a router) to protect your network, but you should also use a software firewall on each computer in your home to help prevent the spread of a virus in your network if one of the computers becomes infected.

Software firewalls are easy to install and protect your computer from malware, cookies, email viruses, pop-up windows, and more. Along with desktop computers, mobile devices can be installed with firewalls to protect online activity on the go.

If the firewall you install does not work for you, you can try others, but you cannot run two different firewalls at the same time.

To uninstall a firewall and try a new one, go to Start, scroll down to Windows System > Control Panel > System and Security > Windows Firewall. Select Turn Windows Firewall on or off. You might be asked for an admin password or to confirm your choice.

Have you purchased specialist firewall protection for your computer? Or do you use the default firewall? Have you ever had an issue with viruses or malware making it through your firewall?

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Written by Ben


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