By Prince McLean

Published: 08:00 AM EST

Leading anti-virus software producers Symantec and McAfee will face new competition in the lucrative market for fixing Windows when Microsoft launches its own free security service, dubbed Morro, sometime in the second half of 2009.

Three years ago, Microsoft unveiled Live OneCare, the corporation’s first attempt at entering the billion-dollar market for software to protect Windows PCs. It tanked as a paid subscription service, which offered users a free 90 day trial period before forcing them to activate the product and begin paying annual fees.

The service was criticized for being unable to detect a significant number of threats, with one site ranking the service dead last among a comparison of 17 anti-virus services. Last spring, Microsoft acquired Komoku and merged its computer security software in the OneCare service.

Now, the company hopes to provide a stripped-down version of the product for free in order to counter the issue of viruses, spyware, rootkits, and trojan malware that plagues the company's software platform, a problem Apple has regularly cited in its advertisements as a reason to "Get a Mac."

Amy Barzdukas, the senior director of product management for Microsoft's online services stated, "this new, no-cost offering will give us the ability to protect an even greater number of consumers, especially in markets where the growth of new PC purchases is outpaced only by the growth of malware."

Symantec and McAfee are experiencing strong growth trends and have for years, despite the availability of software like Microsoft’s OneCare and other free alternatives. However, with Microsoft bundling a free version of its anti-virus service with Windows on PCs before they hit the shelf, consumers will have fewer reasons to look for paid anti-virus services or other free alternatives.

That might likely result in the collapse of a viable commercial market for delivering Windows malware tools, eventually giving the company the ability to charge for the product it could not successfully sell in the presence of competition. Both Symantec and McAfee cried foul over changes Microsoft made to secure Vista which they worried would impact their business. However, both companies are now expressing official confidence that the new Morro won't affect their sales, even as the announcement caused dips in their stock.

The two companies also just settled a complaint that claimed they had "renewed software subscriptions without customers' knowledge or authorization" according to an article published by Reuters citing New York Attorney General Andrew Cuomo. Reuters reported that under the terms of the settlement "both companies will make detailed disclosures to consumers about subscription terms and renewal policies, and each company will pay $375,000 in penalties and costs."

Anti-virus vendors have recently eyed growth in the Mac platform as a potential opportunity for expanding outside of Windows, but the lack of any significant malware threats and the problems associated with installing third party security services has largely kept Apple's customers out of reach. Apple bundled McAfee's Virux tool with its .Mac service until the flood of complaints from users resulted in the buggy, performance sapping product being pulled.

Leading Mac security experts, including CanSecWest winner Charlie Miller, have recommended against installing extra security software on the Mac due to the cost and performance overhead it eats up. "I don’t think it protects me as well as it says," Miller told Computerworld in an interview. "If I was worried about attacks, I would use it, but I’m not worried."