From...

March 29, 1999
Web posted at: 3:25 p.m. EST (2025 GMT)

ALSO    Massive e-mail virus outbreak spreads like wildfire    Copycat virus follows quickly on Melissa's heels    For more computing stories  IN-DEPTH SPECIAL    Insurgency on the Internet

by Stan Miastkowski

(IDG) -- Whether you call it "Melissa" or "Mailissa," it's becoming clear that this PC virus--or worm--is the most widespread we've seen to date. According to antivirus researchers, Melissa first appeared Friday in a sexually oriented newsgroup, and was (it seemed) everywhere on the Internet in a matter of hours.

Melissa is a Microsoft Word macro virus that infects your PC as soon as you open its e-mail attachment. Because it grabs names from Microsoft Outlook address books and resends itself, it has the potential of causing a domino effort of cascading e-mail messages that can bring even the largest mail servers to their knees. Some companies have shut down their outgoing mail in response.

Companies that make antivirus software spent a busy weekend coming up with updates that detect and remove Melissa.

Protect yourself

Although Melissa is one of the most "successful" viruses ever, you don't have to be a victim.

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Melissa messages come with a subject header that starts "Important Message From," followed by a name. The name may be a familiar one to you, especially if it pulled your address from a computer of a friend or business associate.

The message text says, "Here is the document you asked for ... don't show anyone else ;-)."

If you open the attachment, your PC will be infected. If you delete it, you're safe. And if you don't use Microsoft Word 97 (or the prerelease version of Word 2000), breath a sigh of relief: Melissa can't infect your computer.

If you use Word 97 or Word 2000, but don't use Microsoft Outlook, Melissa can't grab your e-mail addresses and propagate itself. But it can still infect your computer, and while it doesn't appear to do more than send out more such messages, its other potential effects aren't completely understood yet.

It's not yet clear whether Melissa can get e-mail addresses from Outlook Express.

One particularly troubling possibility (not yet confirmed) is that the virus may randomly send your own Word documents to others. And it doesn't take much thinking to consider the trouble that could cause.

Taking other steps

Whether you have antivirus software on your PC, you can disable automatic macro execution in Word 97. Select Tools, Options, General and make sure the "macro virus protection" box is checked.

All major antivirus software companies have updates that handle Melissa. If you are running antivirus software, you should update it immediately. (Direct update links for major makers are at right.)

If you don't have antivirus software, consider downloading the free trial software offered by many companies.

To make sure that your PC hasn't been infected by Melissa, go the Trend Micro's HouseCall site, which will perform a virus check on your PC via the Internet.