The Pikachu virus is believed to be the first computer virus geared at children. It contains Pikachu from the Pokémon series, and is in the form of an e-mail titled "Pikachu Pokemon [sic]" with the message: "Pikachu is your friend."The actual virus is in an attachment to the email, a file named "PikachuPokemon.exe".It has "an image of a pensive Pikachu", along with a message stating, "Between millions of people around the world I found you. Don’t forget to remember this day every time MY FRIEND."It was often compared to the Love Bug, though the Pikachu virus was noted to be far less dangerous and slower in its dissemination.
The virus is believed to have been started on June 28, 2000 by someone in Asia or the Pacific Ocean region. Its main form of spread is "through Microsoft Outlook email attachments or through Microsoft's Internet Explorer browser", where it managed to infect "a small number of US companies"
When the user clicks on the attachment, PikachuPokemon.exe adds the lines "del C:\WINDOWS" and "del C:\WINDOWS\system32" (which delete two critical directories of the Windows operating system) to the file "autoexec.bat", which is executed at next boot. The virus was not well coded, so it would give a prompt asking if the user wanted to delete those folders.It is due to this defect, many believe, that the virus did not become more widespread and cause more damage to computer systems