When AV-Test.org repeated a certification test for antivirus protection under Windows 7, the results were almost uniformly worse than in the Windows 7 test from several months ago.

Last year German antivirus test lab AV-Test.org initiated a series of certification tests for antivirus product on different Windows platforms. They rated each product on protection (detection of static and dynamic malware), repair (system disinfection and rootkit removal), and usability (small performance impact and low false positives). A product could earn up to 6 points in each category, with a total of 12 out of the possible 18 points required for certification.

The test series launched in the second quarter of 2010 with certification testing under Windows 7. In the third quarter they tested products under Windows XP. The fourth quarter brought certification testing under Windows Vista. I on the surprising differences some products displayed from one Windows platform to the next.

In the first quarter of 2011, AV-Test.org once again evaluated antivirus products under Windows 7. The results were almost uniformly worse than in the initial Windows 7 test. That's especially surprising because starting with this test and continuing through 2011, AV-Test requires just 11 points for certification, down from the earlier 12.

New Participants

Several vendors have joined the test group since the previous certification under Windows 7. , , , Sophos, and are all first-timers for Windows 7 testing. Of this group Sophos, VIPRE, and eScan achieved certification, with 13.0, 12.0, and 11.5 points respectively. Comodo's 10.5 points and CA's 9.5 points didn't make the cut

New Failures

Several products that achieved certification in the first Windows 7 test would have failed the second time around had the cutoff for certification remained at 12 points. , , and just made the cut with 11.5 points. only earned 10.5 points this time around. In the first Windows 7 test Microsoft pulled in 14 points and PC Tools 13.

The one bright spot is . The first time around it got 11.5 points, just missing certification (which required 12 points at the time). This time, with 12.5 points, it edged into the winners' circle.

Little High, Little Low

The overall big winner in the current test is . With 15.5 points it outscored all the rest and beat its own previous score of 14 points. Almost every other product fared worse this time around, not merely those that sank from certified to uncertified.

, , and ruled the last Windows 7 test, all attaining a total of 16 points. This time Norton got 15 points and the other two just 14. Quite a few others lost a full point or more.

Averaging the most recent test on each of the three platforms, the current top scorer overall is , with 15.67 points, closely followed by Norton with 15.5.

Andreas Marx, CEO of AV-Test.org, notes that the big drop mostly came in repair scores. "Today's threats are much harder to remove completely," said Marx, "as they are often linked to several start-up entries in Windows in order to ensure that they are getting loaded on the next reboot. The anti-malware products are still fighting hard against these critters, but often fail." Marx recommended that users boot from a rescue CD in such cases, to allow repair when the malware is not active.

For a full listing of results from all tests in this series, with links to detailed information about individual products, visit the AV-Test.org Web site.

Lab Test Summary

Making sense of these and other independent lab tests can be tough. I've recently come up with a method to aggregate of tests from five major labs. The chart below summarizes the latest results including earlier this week and today's new data from AV-Test.org. I've included only products that were present in one of these two recent tests.