Computer Security information website. Easy to understand and use. Click this icon:

Computer Viruses

Unless you are an experienced computer user and well aware of computer virus issues, please read everything on this page, twice. And then do it! Several of our readers and Staff have had very bad experiences with viruses. I have Norton Antivirus 2002 running constantly, which finds an incoming e-mail virus every couple of days, and also checks my outgoing e-mails for viruses!

Please heed our advice before your computer becomes a victim!

Werner

Note that this page opened in a new window on your computer, so that you can leave it open for later reference. DO NOT CLICK THE BACK BUTTON TO RETURN TO THE TRUMPET! Just close this window when you're done with it.

What is a Computer Virus?

Computer "viruses" are small computer programs that may just cause mischief or may create havoc on your computer when they "run" or are "opened." A virus can get into your computer from:

• The Internet, usually through an e-mail attachment.
• A floppy disk which has the virus on it.
• A computer network, if your computer is connected to one.
• Any other device which allows external input, such as Zip drives.

What if I get a "Virus Warning" E-mail Message?

Almost all such messages are hoaxes. If you aren't absolutely sure that the sender knows what he or she is talking about, don't take any action that the message recommends and don't pass it on until you check it out (see below). You could easily end up deleting a legitimate Windows file that could cripple your computer!

Check for Hoaxes!

McAfee maintains a list of virus hoaxes here:

http://vil.mcafee.com/hoax.asp

Symantec (Norton) maintains a list here:

http://securityresponse.symantec.com/avcenter/hoax.html

The Klez Computer Virus

This particular virus arrives in emails from virtually anyone, including people you know! It usually has some subject header that you find unusual from that sender.

More than likely it did not come from the person who is shown as the sender. The Klez virus is on someone's computer that also has our addresses, as well. The virus can send itself to anyone in that address book and make it look as though it came from any other address in that same address book. It can even make up a phony email address and claim that's where the message came from.

What if I get a Virus that my Anti-virus Software Doesn't Recognize?

This is very unlikely to happen because viruses take time to spread over the Internet, and McAfee and Norton are constantly searching for new ones to add to their Virus Definition Files, which you download to protect your computer.

How Can I protect My Computer?

The Cardinal Rule for E-mails is: DO NOT OPEN ANY ATTACHMENTS to an e-mail unless you know the sender and the file extension is not ".exe." Even then, be careful if you don't usually get attachments from that person, or if the attachment has an "inviting" name, no matter how tempting it looks.

VERY IMPORTANT regarding e-mails: Make sure that the sender, your friend or other sender known to you, has included a message in the e-mail body that you believe has been written by the sender! That way, you can avoid viruses that automatically send themselves from an infected computer without the computer owner's knowledge.

Some viruses, once activated, send themselves to everyone in that computer's address book! You can always reply to the sender and ask if the attachment was really sent by the sender!

Having warned you about E-mails, the only way to really protect your computer is to have "anti-virus" software running on it. This involves:

• Purchasing the software (usually less than $50). Leading brands are Norton (by Symantec) and McAfee. Beware of any "free" anti-virus software - you get what you pay for.
• Installing it and allowing it to "run" all the time. Turn it off only when installing new software.
• Keeping the "Virus Definition Files" updated.
• Keeping your subscription for updates in force (you have to renew your subscription periodically, for a very small fee).

How Does Anti-virus Software Work?

The anti-virus software scans all files that enter your computer from the Internet, floppy disks, etc. and compares them with "virus definition files" that it has available. When it finds a virus, it will warn you and tell you what needs to be done.

New viruses are constantly being developed and distributed. As the anti-virus software companies become aware of new viruses, they update their "virus definition files" and make them available to you through subscription - but you have to download the updated files through your anti-virus software to keep your copy of their "virus definition files" current.

Updating should be done at least once a week by opening your anti-virus software (right click its icon at the bottom right, in the task bar) and clicking "Live Update" or whatever terminology is used by your brand. Norton Antivirus 2002 automatically checks for updates when you connect to the Internet.