5 years ago... Worm virus ravages corporate networks

11.06.99: A virus which has been described as being "bigger than Melissa" is currently rampaging through corporate email servers across the US and Europe.

Even technology industry giants have picked it up - an unnamed source from the security industry told silicon.com this morning that Lucent Technologies is under siege from the virus and suspects that Microsoft and Intel could be suffering the same fate.

Unlike Melissa, the Worm.ExporeZip virus is malicious and could delete Microsoft Word, Excel and PowerPoint documents from the user's PC, according to security specialists.

11.06.04: Expore. It's not one that lived long in the memory really. Not like Melissa and the Love bug. But this was the time when the idea of the computer virus was starting to grab mainstream attention.

By the time an email arrived, subject line 'I love you', the computer virus was front page news and the hype which surrounds each outbreak has continued until this day.

Along the way there have been more worms that fizzled out and failed to take effect but in the main the arsenal of the virus writer has become more sophisticated. So has the social engineering methodology behind getting users to click on the attachment - with virus writers using everything from fears about the SARS virus to the war in Iraq and famous female celebrities to tempt idle clickers.

Last November marked the 20th anniversary of the very first computer virus and it would appear that malware is here to stay.