Microsoft's Windows Live OneCare security suite has been rated at the bottom of the league in the latest industry antivirus tests.
In extensive testing by AV-Comparatives, an Austrian project set up to test different security products, OneCare antivirus was the only product to fail to achieve any kind of certification, leading the report's author to suggest that he might leave Microsoft's product out of future tests.
"Microsoft OneCare performed very low in the test and did not reach the minimum requirements for participation," Andreas Clementi wrote in the report (PDF). "Due (to) that, its inclusion in future tests of this year (will) have to be re-evaluated."
The report follows closely on the heels of another embarrassing study on Microsoft's antivirus software, when Virus Bulletin tests showed that OneCare failed to completely protect users of Vista, Microsoft's latest operating system.
In AV-Comparatives' test--which covered 16 antivirus products--OneCare came out at the bottom of the list in every category. It scored a 91 percent success rate for detecting Windows viruses, macros, worms and scripts, 79.6 percent for detecting back doors, Trojans and other malware, and 82.4 percent for its overall detection rates.
The highest scoring antivirus packages in the tests were Gdata AVK, TrustPort, Avira, F-Secure, Kaspersky and eScan, all of which scored an "Advanced+" rating.
Microsoft responded to OneCare's certification failure on Wednesday, arguing that it is "looking closely at the methodology and results of the test to ensure that Windows Live OneCare performs better in future tests and (to) determine whether any learnings from these tests can be used to improve our services as part of our ongoing work to continually enhance Windows Live OneCare to ensure the highest level of protection and service that we can provide our customers."
Microsoft also noted that OneCare is "still certified" by the International Computer Security Association (ICSA) Labs and the West Coast Lab's Checkpoint certification system.