Four months and $50 for OneCare

The service will cost $49.95 for an annual subscription, but beta customers who become subscribers in April can purchase the product at a promotional rate of $19.95 for the first year, the company said.

OneCare Live is promoted as a simple all-in-one security blanket for PCs. The product includes anti-virus and anti-spyware protection, a two-way firewall, automatic updates, computer maintenance functions and file backup and recovery capabilities.

"Windows OneCare Live eases the frustration of protecting your PC and gives consumers greater piece of mind so they can spend less time worrying and more time doing the things they enjoy," said Ryan Hamlin, general manager of Microsoft's Technology Care and Safety Group.

Microsoft said hundreds of thousands of beta testers have reviewed the product since November. Based on their comments, the company said it added features, including backup for external hard drives.

Some antivirus companies ridiculed the planned release of OneCare, saying Microsoft should instead focus its attention on providing safe software. Others welcomed the challenge, saying the increased competition will generate more security awareness among consumers.

More than two years ago, Microsoft bought its first antivirus technology from Romanian developer GeCad Software. The company has since acquired Giant and Sybari.