Symantec's Norton Antivirus 2007 is a solid performer, with an overall virus detection rate of 96 percent, placing it firmly in the upper echelon of the test group. Like our other top products, it sports an attractive and easy-to-use interface. It was the slowest to respond to virus outbreaks, however, taking 10 to 12 hours on average to deliver new signatures. And, like Kaspersky Anti-Virus 6.0's, its proactive protection is only middling: it caught about half of the unknown threats in our test.

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Norton performed well in our disinfection tests, second only to Kaspersky Anti-Virus 6.0. It cleaned up 18 out of 22 possible items, missing only one of the two changes to the Hosts network settings file and three less-important Registry items.

Symantec has incorporated the new SONAR behavioural analysis technology for proactive protection. The program scans both email and web traffic, covering the POP3, SMTP, and HTTP protocols. And it ties into the MSN, Yahoo and AOL instant messaging programs (though it protects only MSN by default).

During our testing under Windows Vista Ultimate of Norton AntiVirus's design and ease of use, the program turned off the built-in Windows Defender antispyware utility without notice. This is not because the utility conflicts, according to the company, but because Symantec feels 'Windows Defender offers no value beyond what Norton offers.' BitDefender was the only other program to disable Defender when it installed.

Symantec Norton AntiVirus 2007 was also the only program that triggered multiple UAC (User Account Control) alerts when we changed settings, which could easily annoy power users more likely to customise the app.

Test results and verdict on the next page >

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