Wake up, computer users! The industry and media have been preaching to you for years about protecting your computers -- but many of you are still not doing it. The newly released study by America Online and the National Cyber Security Alliance pushed you out of the closet.

		Previous coverage Downloading games can jeopardize your privacy (5/31/01) No riddle to this case, just outright deception (10/2/03) Spyware no joke, as 2 stories reveal (10/16/03)

This study, which included both surveys and actual scans of home computers for viruses and spyware, shows that most people think they're safer than they are; that they haven't taken the proper precautions; and that many of them have been infected without even knowing.

Eighty percent of the systems scanned during the AOL/NCSA survey had spyware residing on them. The most common spyware found were Alexa (42 percent of the systems) and Claria/GAIN/Gator (26 percent). Yet, in the survey, only 11 percent of the respondents knew that these and other spyware files were on their systems.

So how did they get there? The survey didn't really delve into this question -- but it gave us a great clue: The number of spyware files on systems that also have file-sharing programs (such as KaZaA) have 50 percent more spyware files than the systems that don't have file-sharing programs loaded -- 120 on average vs. 82 for the nonfile-sharing systems.

In May of 2001, in this column, I warned you about Gator. This software is often bundled with freeware games. When you download and install the "free" games, you also install Gator, a spyware package that watches as you surf the net, then substitutes its own advertisements for the ads you would normally see on the publications you're reading online. It's stealth advertising in its grandest glory. Claria, the company formerly known as Gator, substitutes competing ads -- an airline for an airline; a toy for a different toy; one brokerage for another.

Publishers cry foul because the ads they are selling don't get delivered when they should. And Claria is making money on the publishers' copyrighted content. From the user's perspective, it keeps them from seeing items the publisher is putting in front of them -- and of course, it also puts software on their systems they don't know about.

But let's not blame Claria for the whole problem. You, the user, should know that Claria/Gator is loaded on your system. At installation time, it tells you -- and it gives you the opportunity to reject the Claria license agreement, in which case Claria won't install on your system. Neither will that game or other software. So you probably accepted Claria, because it was the easy thing to do. You didn't have to fight with your child about not loading it. (Take it from me. That's a hard battle that I have fought several times with my children. It never feels good to win it.)

Alexa, now owned by Amazon.com, was originally shipped as part of Internet Explorer, and follows you around the Net collecting information about your surfing habits. This information goes into a master profile about you and about various Web sites. In return for this information, Alexa gives you the ability to find pages like the one you're currently viewing. Good concept, if it wasn't so devious in the way it collects information about you.

The AOL/NCSA study shows us that we (Internet users as a whole) are not aware enough about what we install and the dangers we face -- despite the warnings, and our acknowledgements of the potential problems they might cause.

So upgrade those virus definition files; install and use spyware detection software often; and keep those eyes open for unusual system behavior -- like slowness, lots of disk activity, and pop-up windows. They're warning signs.