What is a computer virus?

A computer virus is a piece of software (a computer program) created by someone with bad intentions to purposely damage or confuse computers and computer systems.

How do they work?

Viruses work in a multitude of different ways: they can damage important operating system files, they can collect important information about the users of the computers the viruses infect and send it back to the author, they can produce annoying pop-up advertisements (even when you’re not on the Internet), they can crash websites, and pretty much anything else you can imagine. After infecting your computer, they spread themselves to other computers by using your Internet connection when you’re online. Viruses almost always spread themselves. They can send emails (without you even opening your email program) to everyone in your address book from you that contain the virus. They can also spread through other connections that your computer maintains to the Internet.

How do I get infected?

Most viruses infect computers through application files of some kind (attachment files with a .EXE or .SCR extension are the most typical). The user of the computer (you) has to physically open the application file. Most viruses come through as an attachment to an email message. However, since 2003, viruses have become more advanced and can actually infect your computer through open connections to the Internet.

Why do people write them?

People can write viruses to collect important information (like credit card numbers) for malicious intent, to see how many computers they can infect and, in some cases, people write viruses to crash websites (like the Blaster worm of August 2003 which was written to crash Microsoft’s website).

Are Macs safe?

No. Macs are no longer safe. In the past, virus writers targeted Windows computers because there are more computers with Windows than there are with Apple’s Operating System. However, Apple’s new operating system (OS X or OS 10) is based on UNIX, an operating system that has often been the target of virus writers as it is widely used in major businesses. Because of this, virus writers have figured out how to infect Macintosh computers and write almost as many viruses for Macintosh computers as they do for computers that use Windows.

Are broadband (cable, DSL, or other direct connection) users more at risk?

Yes, but only slightly. Because most viruses are spread via email, Dial-Up users are just as likely to receive an email message with an infected attachment as broadband users are. Viruses that infect computers through other forms of Internet connections are more likely to find and infect broadband users because cable and DSL connections are always on.

How can I protect myself?

Get a virus scanner. In the old days, saavy computer users could avoid catching viruses by being extremely careful. This is no longer the case and every computer should be equipped with up-to-date virus scanners. Computer Mechanix uses Norton AntiVirus exclusively for both Windows and Apple computers. In addition to using a virus scanner, be very careful about opening application files that are attached to emails. Emails sent by viruses are often very conspicuous. Though they will often come from someone you know, the email itself will be very suspicious. A good rule-of-thumb is to simply avoid opening attachment applications unless you’ve spoken with the sender on the phone or in-person and they’ve told you they’re sending you an application in your email. It's extremely important to remember to update your virus definitions regularly. Newer versions of Norton will auto-update, however it doesn't hurt to check your program to make sure it has recently-dated virus definitions (anything over ten (10) days old is too old).

Are all virus scanners created equal?

No. Be very, very wary of trusting online virus scanners. They are not as efficient as scanners that you install directly on your computer. In addition, Computer Mechanix has found that virus scanners made by companies other than Norton are often not as effective at catching viruses, or, in some cases, can cause other problems to your computer (like preventing you from accessing the Internet entirely or, worse, crashing your operating system).

How do I know if I have a virus?

A good rule of thumb on this subject is that if you think you have a computer virus, you probably do. Viruses interfere with activities on your computer from slowing it down to regularly accessing your email program. If you're seeing strange things on your computer (lots of popups, Norton AntiVirus popping up over and over again, etc.) then you probably have a virus. Have no fear, however, as Computer Mechanix can repair any computer with, in most cases, no loss of data. Call Computer Mechanix at 828-281-4379 or make an appointment online.

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