Microsoft's own anti-virus software was one of several Vista-compatible programs that failed to sniff out all the malware currently loose in the wild, a noted testing publication said Friday.

"Virus Bulletin," a U.K.-based publication whose VB100 tests are considered one of the benchmarks of the anti-virus industry, put 15 Vista programs up against January's WildList, a dynamically-updated master list of all viruses, worms, Trojans, and other malware currently spreading. Five failed the test, including Microsoft Windows Live OneCare 1.5 and McAfee VirusScan Enterprise 8.1i.

"They missed viruses on the WildList," says John Hawes, the technical consultant at "Virus Bulletin," and the one in charge of the VB100 testing. "To receive the VB100, they have to detect every virus.

"It's fairly unusual that so many failed the test," adds Hawes. "Before this, there were only three that failed in the time I've been here [June 2006]. Most likely [the problem] is in the signature databases of these programs, but then, a lot of these were still in beta when we tested them."

Microsoft didn't refute the results, although a spokesman said: "We are looking closely at the methodology and results of the test to ensure that Windows Live OneCare performs better in future tests."

Among the 10 programs which passed were F-Secure's Anti-Virus for Vista 2007, Grisoft's AVG, Sophos Anti-Virus, and Symantec's AntiVirus.

OneCare for Vista launched Tuesday, the same day that the new operating system debuted for consumers.