This virus is believed to have been written by a student at the "Vish Finansovo-Stopanski Institut" in Bulgaria. It can be stopped by making files read-only. When it activates, it may display the following messages.
HELLO!!! HAPPY DAY and SUCCESS from virus 1.1 VFSI-Svistov
Allow F-Secure Anti-Virus to disinfect the relevant files.
For more general information on disinfection, please see Removal Instructions.