Safe and secure

Configuring Zonealarm
One of the most popular free firewalls available is Zonealarm, and you can download it free at www.computeractive.co.uk/2128997. By default, Zonealarm offers good protection from internet attacks.

During installation it will automatically decide which programs on your PC should have access to the internet; generally speaking, the majority of users won’t need to alter this. However, should you need to, it’s also possible to manually add or remove internet access for specific programs.

To do this, open Zonealarm and click on the Program Control link. You’ll notice two tabs at the top-left of the window – ­ click on the Programs tab. Now click on the Add button at the bottom and locate the executable (.exe) file of the program you want to allow or deny access.

The new program will appear in the list, with question marks in the Access and Server sections. Click either of these to change the status to Allow, Block or Ask. If you choose Ask, Zonealarm will ask for permission each time access is attempted by this application.

Giving an application Access privileges means that the program will be allowed to connect to the internet and download data. Server access, on the other hand, means the program can listen and accept unsolicited information from the internet, which isn’t something most programs will need.

Before you block access to a specific program, it’s important to make sure it’s not a valid application. For example, some anti-virus applications have a variety of components running under unusual names. Block one of these and you could end up being at greater threat of attack.

If you’re unsure, it’s best to do a bit of research first. Typing the application name into Google usually returns a number of sites that give you more information about it, helping you decide whether or not to block it.

Adding devices
Should you have any standalone network devices, such as a network hard disk, you will need to register them with your firewall to allow the PCs in your network to access them. Adding devices with Zonealarm isn’t a tricky process, although you will need to know the IP address of the device in question.

If you don’t know the IP address, consult the device’s manual – it will be something along the lines of 192.168.1.2 (it’s usually the fourth part of this number as separated by the dots that changes for each device on your network).

Once you have the IP address, open Zonealarm and click on Firewall. Click on the Add button in the bottom-right corner and, from the resulting list, select IP Address. Now enter the network hard disk’s IP address, give it a suitable name and click OK. The drive will now be listed as a trusted source and Zonealarm will allow all PCs in your network to access it.