Windows Live OneCare, Microsoft's new PC maintenance service, wraps a polished interface around a set of security tools that have few configuration options and some performance weaknesses.

We tested only the antivirus, firewall, and antispyware portions of a beta version of Windows Live OneCare. The service, which will launch commercially in June, also comes with PC backup and tune-up tools for a well-priced $50 annual subscription fee for up to three PCs. OneCare does not include antispam features or parental controls.

OneCare offers few configuration options, as it is for people who want Microsoft to manage their security software for them. You can turn antivirus and antispyware protection on and off, and you can set a basic security level (Off, Auto, or Prompt) for the inbound and outbound firewall. While you can initiate a manual malware scan whenever you like, the scheduled scan is tied in with OneCare's other PC utilities; if you want to arrange, say, a weekly malware scan, you'll be setting up a weekly disk tune-up as well.

As of press time, Windows Defender, which provides Windows Live OneCare's antispyware protection, is not yet fully integrated into OneCare. It is a separate software install, and it delivers automatic software updates only twice a week. (OneCare's virus signatures are updated daily.) Microsoft says that Windows Defender will be more fully integrated when OneCare comes out of beta.

In performance tests conducted by AV-Test.org, OneCare displayed some weaknesses. First, it failed to detect 14 out of 1690 file viruses on the WildList, a published list of common malware; since these viruses are publicly known, you should expect your security software to score 100 percent here. Also, among the ten security suites we looked at, OneCare received the worst score in our heuristics tests, which suggests that the program has a hard time detecting malware that it can't recognize through signature files. That said, Windows Defender is meant to be able to block an unknown piece of malware solely based on the way the file interacts with the PC. We did not test this capability, and AV-Test has no data on it.

Windows OneCare scores points for its ease of use. It's a no-hassle way to combine hard-disk maintenance, file backups, and security, but it doesn't offer the best malware protection available right now.

Narasu Rebbapragada