In some ways, antivirus services do family PC owners a disservice: They give us a false sense of security. And the security is increasingly fragile, Washington Post security writer Brian Krebs reports. Citing a candid report from Russian antivirus company Kaspersky Lab, Brian writes, “By the time those [antivirus] products are updated to detect the latest threat, the virus writers have already released several newer versions that evade the latest antivirus signatures.” Brian and a lot of experts are all saying that, though we can’t give up on antivirus protection, we have to understand it’s flawed (ever more so). One security blogger mentions an old joke about the most dangerous part of a car being “the nut behind the wheel” and says nothing replaces educating computer users: “Don’t open attachments, even if the message claims to be from someone you know, unless it was an attachment that you were expecting. I used to say, unless it was about something that you have discussed with that person, but realistically the varied subjects and techniques of virus writers make that too risky.” That goes for attachments to emails or IM, and our kids also need to be very careful about what links the click on. Trojan software can now be downloaded just by going to malicious Web sites. For more, see “Tips from a tech-savvy dad: IM precautions.” And for the latest help in PC protection and clean-up, do not hesitate to take advantage of Microsoft’s free new service, Windows Live Safety Center.