Labs

AntiVirus 2005 is an elegant program that detected every nasty file we could muster. Previous versions have been less successful, so we were pleased to find that it's better at detecting customised files. It found every infected e-mail and deleted every attachment, replacing each Trojan, worm and script with a text file containing their names.

While it didn't miss any viruses, it made a real fuss about finding them. When you download e-mail the scanner checks each message, one at a time. It pauses the download while it checks the file and lets you know it's found something. This means you have to click an acknowledgment for each virus it discovers. If you walk away while downloading your mail, you'll find on your return that the connection has timed-out thanks to Norton AntiVirus's indecision.

AntiVirus has a feature that monitors JavaScript and Visual Basic scripts for bad behaviour. It certainly did the job on ours. Thankfully, you can tell it to ask permission before killing off scripts, which is useful if you use scripts regularly. The script-blocker won't spoil your Web browsing, and doesn't prevent legitimate Web site JavaScript scripts running

The main problem we have with Symantec's anti-virus software is the frequency with which it receives virus definition updates. Viruses spread very quickly over the Internet, so you need to act fast. But Symantec's automatic updater, known as LiveUpdate, doesn't download the latest definitions every day, as many of its competitors do - even if you set it to do so. LiveUpdate definitions are updated weekly, whereas Kaspersky provides three sets of updates a day. In the past we've received viruses that were newer than the latest Norton LiveUpdate definitions.

If you want daily updates, you have to visit Symantec's Web site and download and run an installer called the Intelligent Updater - every day. Symantec doesn't expect home and small business users to bother with this, so it doesn't shout about the Intelligent Updater. In fact this may be the first you've heard of it. If you use any version of Norton AntiVirus, we recommend that you perform this onerous task while petitioning Symantec to update its LiveUpdate definitions at least daily.

The software comes on a bootable CD, so you don't need to mess around with rescue-floppies. This is a very useful feature and one that other anti-virus companies would do well to copy. There's no point in wishing you'd created a rescue disk when your PC is being eaten alive by viruses. If you download Norton AntiVirus, and so don't have a CD, you can create rescue disks with a utility included.

Despite our gripes, this is a full-featured program that does a good job of protecting your PC from viruses. It's no better than our two winners, though, and costs more. It's slightly cheaper to run after the first year, but it'll take you a few years before you make your money back.