Microsoft will dump its Windows Live OneCare consumer security software next year and instead give away revamped, streamlined anti-malware software that it's calling "Morro" for the moment.

A longtime rival called the move the equivalent of Microsoft raising the white flag. "We view this announcement as a capitulation by Microsoft, and a reinforcement of the notion that it's simply not in Microsoft's DNA to provide high-quality, frequently updated security protection," said Rowan Trollope, senior vice president of Symantec's consumer software, in an e-mail Wednesday.

Morro, which will rely on the same scanning engine that OneCare and other Microsoft security products currently use, will be available in the second half of 2009, said Amy Barzdukas, a senior director of product management at Microsoft. The software, she said, will provide a "basic level of anti-malware protection," including defenses against viruses, worms, Trojan horses, rootkits and spyware.

Windows Live OneCare, meanwhile, will get the boot as of June 30, when it will be dropped from retail sales.

Barzdukas cited two reasons why Microsoft decided to take its consumer security software down the free road. "First, the incidence of malware continues to go through the roof," she said. "Malware is also 'quieter' than it used to be, and people have the lowest level of concern over malware since 2004. Users aren't connecting the dots."

Second, she continued, malware infection rates in developing countries are climbing even faster, while people in those places may find it difficult or impossible to find or pay for security software.

Together, those spell trouble for Microsoft. "From an overall Microsoft and Windows perspective, these aren't good for us, and not good for the [Windows] ecosystem," Barzdukas said.

Microsoft has made several moves lately that it has said were driven by a desire to boost security not just in its own products, but to better secure all PCs. In one program in that campaign, Microsoft said it would export its expertise in writing secure code to third-party developers.

"I think [Morro] is consistent with our other decisions" along those lines, Barzdukas said.

Much of Morro is still up in the air, including its exact release date, how it will be delivered and how it will perform. Barzdukas declined to answer those questions, instead saying that Microsoft would reveal more at a later date.

But low impact on PC performance is clearly a goal of Morro. Calling it "slimmed down" in comparison with third-party consumer security software, Barzdukas said Morro will be "lighter and work on less-powerful machines."

Users often complain that security software consumes too much memory, takes too long to load and slows down their PCs' speed, issues that some vendors have tried to address. Symantec Corp., for instance, this year rewrote its Norton consumer line to lighten its system "footprint."

Microsoft's move to free its software could create problems for companies that specialize in consumer security, said Graham Cluley, a senior technology consultant at UK-based Sophos. Although Sophos develops security software, it doesn't sell to consumers.

"There will be some sleepless nights" at companies like Symantec, McAfee and Trend Micro, the three largest consumer security software makers, Cluley said. "They may wake up in a cold sweat."