March 28, 1999
Web posted at: 6:10 p.m. EST (2310 GMT)

NEW YORK (CNN) -- Monday morning could bring some e-mail madness to businesses who've had a weekend visit from Melissa.

The "Melissa macro" is actually a virus -- also known as W97M_Melissa -- and experts say it can hit anyone using Microsoft's Outlook e-mail program. It struck at Microsoft, Intel, and dozens of other companies on Friday, and it's now moved throughout the online world.

Each time the virus is activated, it sends as many as 50 e-mails with a caption saying "important message." Often the sender appears to be someone you know. That's because the virus automatically grabs names from the address book of whoever activates it.

Melissa is running rampant because everyone who gets it potentially could spread it to dozens of others.

Here's how to find out if Melissa's lurking in your e-mail: look for a message that says "important message from ..." and then a name that may be familiar. Don't open it. If you do, inside you would see a message saying: "Here's the important document you asked for. Don't show anyone else" and an attachment called "list.doc."

Don't click on that either. If you do you will receive a list of pornographic Web sites -- and also the virus that will infect the next document you open.

Mail servers could crash

"Any document in your PC could potentially get infected, and if you then happen to send that document to a colleague at work or a friend and they open it, that document will potentially then be sent to up to 50 people in that person's Microsoft Outlook address book," said Steve Trilling of the Symantec Antivirus Research Center.

"This one, from a technical standpoint, isn't dangerous in and of itself," added Ira Winkler of the Internet Security Advisors Group. "What makes it dangerous is that it can spread very, very rapidly and fill up mail servers, causing mail servers around the world to crash."

Symantec and other companies producing antivirus software have devised software patches which are posted on their Web sites.

Carnegie Mellon's Computer Emergency Response Team said all businesses and governments must take precautions against the potential security breach. The team has issued only one other worldwide warning since it was founded 10 years ago.

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