Do the names Melissa, I Love You, Love Bug or Anna Kournikova ring any bells for you? They are all viruses -- malicious programs that can and do damage data and computer configurations and they have all infected the machines of millions of users over the last couple of years. And these are just a few of the more famous ones. There are literally thousands more, and they are causing expensive damage on computers all over the world, every day. What all these viruses have in common is that they are spread as 'e-mail attachments' files sent together with the actual e-mail message, usually identified by a paper clip symbol or something similar. Just receiving an attachment isn't dangerous, but if you execute it, which means running it like a program, it can basically do anything it wants.
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