First, it is the extremely high speed of distribution. Immediately after infecting the system the virus dispatched letters with copies of itself to all the email addresses in the list of addresses in Microsoft Outlook. This virus is similar to virus Melissa found in spring 1999. Love Letter sent these letters ostensibly, on behalf of the owner of the infected computer who didn't know about it at all.
Secondly, the delivered infected enclosed files disoriented users by the extension: 'TXT.vbs'. The majority of users still think, that text files cannot contain nocuous programs. It is true, however under forged expansion TXT you may find anything you like, in this case it was a program written in Visual Basic Script (VBS).
Thirdly, the author of the virus used a simple and ingenious course from the psychological point of view: a few people can not to read a love letter from their friends. The basic emphasis was made on it during the construction of the virus.
It is necessary to notice, that "Kasperskiy Laboratory" has predicted the opportunity of global epidemic of the script-viruses similar to Love Letter, in November 1998 when virus Rabbit was found out. Then many people accused the company of inflating virus hysteria, however spring 2000 has confirmed all forecasts of the head of anti-virus researches of the company of Eugeny Kasperskiy.