PC security-software bundles can't block them all

Many Windows users worry about viruses. Some also worry about the software that's supposed to protect their computers from viruses.

That second fear comes in two flavors: that a security program will unintentionally sabotage your machine and that it will get more complicated every year.

Once, not too many years ago, you could feel safe with just an anti-virus program.

But over the past few years, security-software developers have kept adding new defenses for new dangers: worms, spyware, spam, phishing and so on.

More recently, by adding tools to back up your data, they've built all-in-one suites that claim to do everything to defend a Windows machine.

The idea is to end your anxieties with a single installation. But after testing three of these bundles — Symantec's Norton 360, Version 2.0; McAfee's Total Protection; and Microsoft's Windows Live OneCare — I wonder whether attaining that goal is possible.

All of these packages include the same defensive lineup of anti-virus, anti-spyware and firewall protection, with side orders of Web phishing filters, data backups and performance tuneups.

McAfee adds spam filtering and parental-control features, while Symantec provides those features in a free, optional download.

Norton 360 and McAfee Total Protection cost $80 a year to run on three computers (McAfee has a $20 rebate), while OneCare runs $50 a year for three PCs.

Norton 360 and OneCare run on Windows XP and Vista; McAfee Total Protection also runs on Win 2000.

For this kind of program, "success" means keeping the PC safe, then keeping out of your way.

To test that fairly, I created a test XP system, with all of Microsoft's patches and a grab bag of other programs, then cloned three copies of it, one for each suite, using the Parallels Desktop "virtual machine" program on a Mac.

(I picked XP over Vista because Vista includes many of these programs' security fixes, such as spyware protection.)

The test revealed one surprise: For all the griping about how security programs can bog down a system, these three did not. Each took up only 50 to 70 more megabytes of memory than the free, anti-virus-only AVG program.

Norton 360 was only slightly more efficient than the others.

But other glitches surfaced. Microsoft's Outlook 2007 mail program froze once in the McAfee and OneCare installations.

Windows itself locked up during shutdown on the McAfee system, and Norton 360 stalled a shutdown when its "ccSvcHst" file wouldn't quit. (Incidentally: Why can't Symantec use real names for these program files?)

Should a known virus land on your machine, you should be able to count on these programs to swat it aside. But Norton 360 took its time issuing a verdict on new downloads and once didn't stop me from installing fairly obvious spyware — which it volunteered to evict afterward.

To Norton 360's credit, it also had the least-intrusive firewall. I never had to change settings to authorize a legitimate program's online activity.

OneCare and McAfee both needed my input before such third-party programs as an Apple CD/DVD-sharing tool would work.

I was least impressed with these programs' anti-spam and anti-phishing tools, which largely duplicated what modern Web browsers and mail programs already include.

If, however, you simply cannot stop yourself from clicking on a Web link, McAfee's SiteAdvisor might be the restraint you need. It not only stops access to many — but not all — sites hosting viruses and phishing scams, it also blocks many sites used by spammers.

That brings up a bigger security issue, one ignored by all three suites: the Internet-connected programs on a PC besides your browser and mail software, each of which can be attacked separately.

None of these programs warned that the test copies of XP lacked important security fixes for Adobe's Flash plug-in, leaving them open to hijacking by hostile Web sites.

Should that happen, causing your computer to get infected and your data to disappear, McAfee might offer the least security of all. Its clumsy, ugly backup tool's default settings left almost all my data unprotected.

Microsoft and Symantec provided simpler, more capable backup programs. But if you run a non-Microsoft Web browser, photo album or music player, you may need to tinker with their settings.

Is the picture clearing up? None of these "do it all" programs does it all sufficiently well. You're better off mixing different programs — for example, pairing the free firewall in XP and Vista with a basic anti-virus program.

Beyond that, the most important security upgrade is in your own head: don't-take-candy-from-strangers skepticism, without which no security program can keep your computer safe.