Opting out of spam gets you even more spam.
You've heard the advice. Don't reply to spam. If you do, you'll get even more because you've just told the spammer that your e-mail address is legit.
"No one has done a complete test of this because it's difficult, if not impossible, to prove beyond a doubt," says Ari Schwartz, associate director for the Center for Democracy & Technology. With spam accounting for as much as 83 percent of all Internet-delivered messages in the United States, he says, "if you do opt out and get more spam, how will you know you wouldn't have received it anyway?"
Sometimes opting out does work. Last year CDT researched spam sources by creating e-mail accounts, seeding them through various venues, noting the amount of spam that each account received, and opting out. Many companies complied with the opt-out requests within two weeks.
"Knowing who to opt out from is key," says Schwartz. "Opting out of legitimate companies drops you off their lists, but when you do that with 'real' spammers, the results are unclear."
Regardless of whether you opt out, spammers have various tools to grab addresses. You can't completely protect your inbox, but you can take defensive measures, such as keeping your e-mail address off public sites, says Schwartz.
Hackers can destroy data on your computer's hard drive.
"The MyDoom.f worm took a step back into an era where viruses actually attacked data," says Bryson Gordon, a senior manager with McAfee Security. Although viruses and worms that attack files are relatively uncommon, they are nightmare number one for anyone connected to the Internet.
Among other nefarious activities, MyDoom.f sniffed around on infected PCs looking for Word, Excel, and graphics files and then randomly deleted some of what it found. Of the people whose PCs got the worm, 40 percent lost Word files and 60 percent lost Excel files.
Today's hackers want to hijack systems, not destroy them. Rather than wipe out data, worms and viruses want intact PCs to send spam or to attack Web sites. "Just like a biological virus, if a computer virus kills the host before it propagates, it can't propagate," says Allen Householder, an Internet security analyst with the U.S. Computer Emergency Response Team, which is now part of the Department of Homeland Security.
Turning off your PC daily to save power shortens its life.
Here's a topic that provokes debate. One side argues that turning the PC on and off stresses components. The other side says it's a good thing; even the best programs and the OS can get cranky without occasional shutdowns.
There's no definitive answer. Most authorities, however, lean toward the idea that shutting off does more good than harm--plus it saves power. Kevin Krewell, editor in chief of the Microprocessor Report, supports that side of the debate. "Processors typically have a ten-year life span," he says, so a PC will be dead weight before switching it on and off could affect the CPU.
Tip: If you're using Windows XP, right-click the desktop, choose New, Shortcut, type shutdown -s -t 00, click Next, give the shortcut a name (for example, Shutdown), and click Finish. Next time you need to shut down, click the shortcut icon.