Trend Micro's low score was primarily decided by its lacklustre performance at detecting malware samples. The program missed almost one in five samples, for an entirely disappointing catch rate of 82 percent.

Trend Micro did somewhat better in proactively detecting unknown malware, but even here it had a poor showing. It caught 43 percent of threats when tested with a month-old scanner. Coupled with a relatively expensive $40 price tag in the US and no renewal discount, Trend Micro's antivirus product left much to be desired. It's currently available in the UK only as part of the PC-Cillin suite.

On the plus side, the program installed smoothly, was easy to use, and includes good default settings for the average person, such as an automatically scheduled full-system scan. It provides a user-configurable scheduled scan and checks for definition updates every three hours. These defaults are a snap to change via an intuitive and smooth interface that will appeal to even the most nontechnical user.

One particularly useful feature scans for known Microsoft product vulnerabilities. If a machine is missing an important security patch, for example, the application guides the user to Microsoft's Windows Update site to download and apply the appropriate updates and patches.

Trend Micro's AntiVirus scans email traffic over the POP3 and SMTP protocols but, unlike almost every other program we tested (except for Grisoft's AVG), it does not scan HTML traffic. Also, it stands alone in being unable to launch a manual file scan when you right-click within Windows Explorer, a weakness in the Vista version that the company says it will remedy in future updates. And the application's antispyware protection has an annoying habit of labelling tracking cookies as dangerous spyware.

Test results and verdict on the next page >

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