Microsoft’s anti-virus security package OneCare has failed independent benchmarking tests, placing it last in terms of effectiveness, behind 16 others.

OneCare detected only 82.4% of the malware used to test it and performed particularly badly with Trojans and backdoor hacks, finding only 79.6%, while it also finished last in all three detection tests.

All the other packages tested except one scored over 90% in picking up the 500,000 malware instances thrown at them by AV comparatives, who published the report. And the best overall system it found, G Data's AntiVirusKit, detected 99.5% of all threats.