According to S!Ri (Merci pour la sample):
System Tool is a new version of Security Tool, Total security 2009, System Security rogue.
This fake anti-spyware tool displays fake alert messages, prevent execution of legit programs, detects inexistent infections and Hijacks desktop background to scare users.
If you need to clean your computer and System Tool is blocking legit cleaner execution, enter this serial to register: WNDS-S0DF5-GS5E0-FG14S-2DF8G
If your PC is infected with System Tool use MBAM to remove the infection.