The key thing to know about Microsoft's own security suite is that it's on its way out. From June it's set to be replaced by a free package, currently known as Morro - so even if we loved OneCare we'd be reluctant to fork out for an annual subscription.
As it happens, though, it's one of our least favourite packages, owing largely to its constant nagging. During our tests it nagged us to turn on automatic updates, to run its system tune-up tasks and to reboot after it had removed an infected file.
It also repeatedly demanded that we should "open OneCare to find out what you should do." We almost prefer the malware to this time-wasting nonsense - it's less intrusive.
OneCare did achieve some decent test results. Its malware detection score of 85% places it only a few per cent behind some serious contenders. It didn't do badly in our web test either - no package came near to AVG, but OneCare's 54% was only 6% off second place. A cynic might conclude that Microsoft knows all about vulnerabilities in Internet Explorer.
You'd also hope that Microsoft would know how to integrate a product seamlessly with Windows, but OneCare was comparatively sluggish, settling down to a merely average memory footprint. It also provided merely average protection against our network attack, revealing five vulnerabilities and two open TCP ports.
The package does include a simple network management module, for checking the security and backup status of multiple PCs. There's an optional online backup service too, though oddly it only lets you back up photographs. But for those who don't need hand-holding it's simply irritating to use, and ultimately a poor investment.