For example, experts estimate that the
Mydoom worm
infected approximately a quarter
-
million computers in a single day in January 2004. Back in
March 1999, the Melissa virus was so powerful that it forced Microsoft and a
number of other very
large companies to completely turn off their
e
-
mail systems
until the virus could be contained. The
ILOVEYOU virus
in 2000 had a similarly devastating effect. That's pretty impressive when you
consider that the Melissa and ILOVEYOU viruses are incredibly simple