It prevents the computer from starting up. It deletes the BIOS information. It infects files with an EXE extension (executable) and an SCR extension (screen savers).

Windows 2003/XP/2000/NT/ME/98/95

Kriz.3863 is a extremely dangerous virus, as it deletes the BIOS memory information, as well as files in all the available drives. In other words, the infected system could stop working.

In addition, when Kriz.3863 runs an infected file, the virus goes memory resident and infects files with the following extensions:

• EXE: executable files.
• SCR: screen savers.

In order to spread, Kriz.3863 uses a wide range of means of transmission. It carries out its most dangerous action on December 25 of any year, which consists of deleting the BIOS.

Kriz.3863 is difficult to recognize, as it does not display any messages or warnings that indicate it has reached the computer.

However, on December 25, after Kriz.3863 has carried out its infection, it will be impossible to start the computer, as the virus will have deleted the BIOS.