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
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
Detailed instructions for F-Secure security products are available in the documentation found in the Downloads section of our Home - Global site.
You may also refer to the Knowledge Base on the F-Secure Community site for further assistance.