Bits & Bytes

Editor's note: Bits and Bytes is written by guest columnist Ms. Lin MacDoss while Susie Cooper is away on vacation. "Healthy Alternatives" with Susie Cooper will return on September 11, 2003. Securing Your Windows Computer by Ms. Lin MacDoss

If you spend any time online, or ever share a file with another computer via a floppy or CD, then your computer is at risk. There is the risk of potentially destructive viruses infecting your system from email attachments, or of other malicious codes being placed on your machine from a seemingly innocent web page. There are also hackers who scan your ports, hoping to gain access to your computer. Once access is gained, the hacker can do anything from destroying your data, recording your keystrokes to gain access to your user names and passwords, to turning your machine into a "bot" (short for robot) to be used in distributed denial of services attacks on key Internet services.

Even though all computers are at risk, machines running any of Microsoft's popular Windows operating systems are especially vulnerable. Microsoft isn't entirely to blame for this; their operating system runs an estimated 95% of all desktop computers, making Windows a tempting target for "script kiddies" and virus writers. Even so, this doesn't mean that Bill Gates and Company are blameless, since their commitment to security has often given way to their desire to make computing brainless for the average user.

If you're a Windows user, however, you don't need to trade-in your computers for a Mac to be safe while checking email or surfing the web. As they say, an ounce of prevention is worth a pound of cure, and taking a few simple precautions now will save you from later computer grief.

To catch viruses, worms and trojans before they have a chance to do any harm, your first line of defense should be a good antivirus package. Since new viruses show-up on the Internet daily, and antivirus programs work by matching definitions of known viruses with files on your computer, it's important that your program be backed by a large research staff to stay on top of the latest threats. In other words, choosing an antivirus package shouldn't be done by price, but by the effectiveness of the software. Suggested programs: Norton AntiVirus, McAfee VirusScan or PC-cillin by Trend Micro. Each sells for about $50.

You should set your antivirus program to start automatically when you boot your computer, and to automatically monitor email, instant messaging and Internet downloads. It's also important that you update your virus definitions weekly. Most programs will do this automatically, but you'll have to set the scheduler to do this.

After antivirus software, your next line of defense should be a firewall program, both to block unwanted intruders from entering your computer and to make your machine invisible to anyone looking for a vulnerable machine to attack. Without a firewall, a Windows computer is clearly visible on the Net, and will actually allow a hacker to gain access on some ports. A good firewall will also protect you if a hacker has already placed a malicious program on your computer, by blocking it from "calling home" or otherwise connecting with the hacker who placed it there.

According to Internet security expert Steve Gibson, the most effective firewall on the market is Zone Alarm, which is available for free from http://www.zonelabs.com. However, if you are sharing an Internet connection with other computers in your home, the "gateway" machine (the computer actually connected to the Internet) will need to use Zone Alarm Pro, which sells for $49.95. After installation, use the default settings of high for the "Internet Zone" and medium for the "Trusted Zone." After doing this, visit the Shields Up web site and click "Test My Shields" and "Probe My Ports." If you have your firewall configured correctly, the results should indicate that your computer is "stealth" and invisible to all port scans.

Your next step would be to quit using any version of Internet Explorer and Outlook Express, the web browser and email client that is included with all versions of Windows, since the vast majority of vulnerabilities in Microsoft's consumer products are found in these two programs. Instead, download Mozilla or Opera. Not only are these browsers available for free, they're superior to Internet Explorer and contain useful features like tabbed browsing not found in the Microsoft product. Both contain email clients for sending and receiving email.

Finally, learn to practice "safe computing." Most computer viruses infect machines when users open the door and let them in. Never open an attachment, either in an email or through instant messaging, unless you've been expecting it and know the person it came from. Because many viruses replicate by sending copies of themselves to everyone in an infected machine's address book, just knowing the sender is not good enough. If you receive an email attachment that you weren't expecting from a friend, email that friend and ask them if they sent it to you before opening it.

Also, don't fall prey to any email with an attachment that claims to be a "cure" for the latest virus on the web. Always, such emails contain the very viruses they claim to eliminate, even when it seems as if the email was sent by one of the large antivirus firms. The makers of antivirus programs never, ever send virus fixes via unsolicited email.