Protecting Your System from Viral Invasions - dummies

Protecting Your System from Viral Invasions

By John R. Levine, Ray Everett-Church, Greg Stebben, David Lawrence

You may not like hearing this statement, but it turns out that Mom was right: When it comes to fighting viruses, it’s much better to take the proper precautions to avoid the virus in the first place than it is to be careless and have to fight the cold or virus later on.

Someday, you’re going to start taking all the proper precautions. Will that day be today, or the day after you lose all your data to a critter?

Even if a fierce, new critter is taking cyberspace by storm and you don’t have the money for antivirus software, if you go to the sites of most antivirus software makers, you can often download a trial version for free that protects you for at least a week or two until the existing crisis is over.

For a trial version of Symantec Antivirus, visit Symantec. For a trial version of McAfee Antivirus, visit McAfee.

If you bought your computer in the past three years, chances are that it shipped with some antivirus software preinstalled on it. That would be a good thing, except that antivirus software stops being current the day it’s slapped on your machine. If you don’t update the virus definitions regularly — at least once a month — you’re really not protected. After all, with antivirus experts estimating dozens of new strains and variations of viruses appearing each month, relying on outdated antivirus software is a bit like placing your faith in a really good suit of Renaissance-era armor when everybody else is sporting a brand new “Star Trek” phaser.

When was the last time you downloaded the latest definitions for your antivirus software? To find out, click on the icon in your Windows system tray (on the opposite end from your Start button, near the clock) or click on the Start button, choose Programs, and look for the name of your antivirus software. If your software doesn’t display the date of its most recent update on the main menu, try choosing About from the Help menu. That should tell you what software version you have and may even say when it was last updated. The same set of Help menus should also give you instructions on how to update those antivirus definitions.

Here are some more ideas to add to your arsenal of infection-fighting actions:

  • Virus-scan every floppy disk that goes into your computer. It takes only a second to scan your floppy disks, and some antivirus software does it automatically whenever you insert a disk, so it’s a no-brainer.
  • Treat attachments with care. Don’t open unexpected files or attachments from people you do know until you’ve confirmed why they sent them, and don’t ever accept files or attachments from people you don’t know.
  • Don’t accept downloads from strange Web sites. Unless the Web site has a good reason for sending you something to download, you’re wise to reject those automatic download boxes that sometimes pop up. If there’s a legitimate reason for making you download some kind of program, Web sites usually tell you well in advance and give you the opportunity to download it yourself rather than force it on you.
    One automatic download that’s usually acceptable: Shockwave Flash plug-ins. Many Web sites use Flash to enable rich menus. But if you’re feeling skittish about accepting downloads from unfamiliar sites, you can always go to on your own and get Flash directly from the source.
    When Web browser plug-ins, like Shockwave, are downloaded, Internet Explorer alerts you to the impending installation and displays an authentication statement. After the plug-in is installed, an animated graphic appears and you can continue browsing.
  • After you download files, scan them. Make sure that you scan all files or programs you download before you install or run them. Even if your favorite shareware Web site claims that they virus-scan everything, take the few extra seconds to run your own virus scan before installing new software. Likewise, you should also take the time to scan all files sent from coworkers and friends before opening them.
    Many antivirus software packages let you right-click on a file to scan it instantly — and now that you know, you also know that you have no excuse not to.
  • Check your macros at the door. Make sure that any programs on your computer that use macros (most commonly Word, Excel, and WordPerfect) have their macro-related security settings set to their highest setting. This setting alerts you to the presence of a macro before it’s executed, giving you a chance to run a virus scan on the file before executing the macro — and to possibly avert disaster. If your software program doesn’t offer a security setting for macros, check with your software vendor for an upgrade security patch.
    To turn macros off in Word 2000 and Excel 2000, choose Tools –> Macro from the menu bar. You should see a Security submenu that enables you to turn macro functions on and off. In WordPerfect versions 9 and 10 (part of Office 2000 and Office 2002), choose Tools –> Visual Basic from the menu bar and then click on the Security tab to select it.