At first glance, not much appears to have changed from version 3. A closer look, however, reveals that the engine in version 4 has been tweaked and optimised towards a more powerfully specified product.

We knew that Outpost Personal Firewall Pro 2 would improve on its predecessor, but this version is a major upgrade. I'm not just talking about the superb revamped interface, which couples simplicity with power, but a quick look under the pretty skin confirms that this is a serious development.

A software firewall has to really stand out to succeed in the crowded market, but ZoneAlarm Pro 3.5 with Web Filtering does just that.

Feature-packed and good value, but it’s slow, has too many pop-ups and a less-than-perfect firewall.

Excellent value for money, but a few performance glitches.

Excellent value for money, but a few performance glitches let BitDefender down.

A truly silent firewall, reduced system impact and an improved interface finally make Norton attractive.

Excellent support, but a confusing user interface and disappointing firewall let AVG down

A best-of-breed approach to Internet security pays off. This flexible and resource-friendly suite returns to the A-List.

With less hand-holding and a greater feeling of control and configuration, Norton is definitely geared more towards the advanced user than McAfee. Although the interface is quite different, it's undoubtedly a more professional product.

With less hand-holding and a greater feeling of control and configuration, Norton is definitely geared more towards the advanced user than McAfee. Although the interface is quite different, it's undoubtedly a more professional product.

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A competent suite delivering good value for money, but it offers only average spyware and spam protection

A three-PC licence as standard, superb silent interface and effective security utilities make Norton 360 a tempting buy.

PreviewA good attempt at all-in-one system security, fully integrated into the OS.

A mixed bag of features, with some fundamentally flawed defaults and too many opaque alerts.

A good concept, but the on-demand anti-virus scanner lacks real-time email and IM protection.

A well rounded package that falls short on security.

Scanning, site blocking and alerts improved over version 6.

Kaspersky's first integrated security suite relies too much on the anti-virus component.