How Did I Send This Virus-Infected Email?

Reader Bradley writes: I got this message about a failed delivery {Subject: [POSSIBLE VIRUS:###] Fw: Delivery Status Notification (Failure)}. I never sent this message. Is this just spam, or do I have a virus. It says I sent the message at a time when my computer was off.

Relax. You almost certainly don't have a virus, and you didn't send the message. A virus has not yet been written that can turn your computer on in the middle of the night and send a bunch of spam messages.

Here's probably what happened: Your email address was used by a spammer/virus-sender. Note: They didn't use your account, they just used your address by forging the sender field. This is extremely common because it is so simple. It's the equivalent of me writing a letter by hand and putting "George Bush, White House" as the envelope's return address instead of my own. This doesn't really fool anyone.

If your email address is short, simple, and/or available online, it's more likely to be compromised by forgers. There's not much you can do about it. This eventually happens to everyone, even those with complicated email addresses. Once you end up in the spammer mailing lists, there's really no way off. Basically there's no point in worrying about it.

The bigger problem here is the recipient's antivirus system, which has been programmed to send out these bounceback messages instead of simply deleting the spam/suspected virus. It doesn't bounce to the actual sender; it bounces to the forgery: You. Sender forgeries are as old as the internet itself, and you would think antivirus system programmers would have caught on by now that sending bounceback replies like this are useless and confusing to people like you who receive them. In fact, they do more harm than good, because often the actual virus is still attached inside the returned email, which you might actually open. It's the circle of life. Virus life. (There are numerous plans in the works to attempt to fix this issue by making forgeries more difficult, but that is slow going.)

Bottom line: The best thing you can do is simply delete this messages and mark them as spam in your own spam filter. As always, make sure your own antivirus definitions are up to date and run a full system scan once a week.

For more info on spam filters...