...Windows Live Search...leads the pack: referrals for sites that actively try to infect end users' machines with some of the vilest malware known to man...According to researchers at Sunbelt-Software, Live.com's affair with malicious sites runs so torrid that malware-related returns on the search engine number in the thousands...

Microsoft has said that its OneCare security suite has "a problem" with the underlying antivirus code, and admitted that security is just "a little part of Microsoft".