Loveletter Worm

Released in 2000 and spread by email attachment, the notorious LoveLetter worm was the most damaging virus to date, infecting millions of computers worldwide. The carrier email disguised itself as a love letter with the subject line "ILOVEYOU", effectively exploiting human nature and tricking recipients into opening it. Users were infected through Internet chat systems, as well as through other shared file systems.

When executed, the worm sent copies of itself to email addresses in the recipient's Microsoft Outlook address book entries. Infection caused the worm to overwrite several types of files, including .gif and .jpg files, to change Registry keys, to modify the Internet Explorer browser home page, to hide MP3 files, as well as to move other user files.