Given the rise in numbers of computer hackers, scammers and viruses around the Internet, you should install a firewall. Data that is entering your computer should be challenged by a firewall. It stops your computer being prone to dangerous attacks that can negatively impact upon you.
Since there are a wide variety of firewalls available, including those from major corporations such as Microsoft, you first need to determine what kind of firewall your PC requires. A firewall is likely to be set up and ready to use if the computer came installed with the Microsoft XP or Vista operating system. However, you do need to make sure that it is turned on and working properly. Purchase your own software if you do not have one of these newer operating systems. You may want to purchase separate software to complement Microsoft XP as its version of firewall doesn't get great reviews.
You can either visit a store that sells computer software or download a firewall product through the Internet - the most popular products available are Norton, AVG and McAfee. There are plenty of low cost versions available, even from the big name companies, with prices varying according to the sophistication of the software. Before your firewall is installed, a few things must be taken into account. The functions that you need, such as file and printing sharing, must not be blocked by the program. This is normally done during installation but can also be done later by using the documentation provided to change the settings.
Parts of the Internet may be restricted by a firewall. You should be aware how you connect as this may happen if you use a local area network or a router. When you have installed a firewall in place, secured networks in particular are difficult to access. A pc linked to a company network may require a specific settings configuration to allow you to connect a firewall to them and the company's IT department should be able to advise you with this.
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