Microsoft to unveil free anti-virus software

Microsoft Corp is getting ready to unveil a long-anticipated free anti-virus service for personal computers that will compete with products sold by Symantec Corp and McAfee Inc.

A Microsoft spokesman said on Wednesday that the world's biggest software maker is testing an early version of the product with its own employees. Microsoft would "soon" make a trial version, or product beta, available via its website, he added, but declined to provide a specific date.

Symantec shares fell 0.5 percent on Nasdaq and McAfee fell 1.3 percent on the New York Stock Exchange, while Microsoft was up 2.1 percent. The Nasdaq composite index was down 0.47 percent.

Investors are closely monitoring the free service, code-named Morro after Brazil's Morro de Sao Paolo beach, amid concern it could hurt sales of products from Symantec and McAfee, which generate billions of dollars of revenue a year protecting Windows PCs from attacks by hackers.

"It's a long-term competitive threat," said Daniel Ives, an analyst with FBR Capital Markets, though he added that the near-term impact was minimal.

Microsoft has said that Morro will offer basic features for fighting a wide range of viruses, which would likely make it comparable to low-end consumer products from Symantec and McAfee that cost about $40 per year.