Free Malwarebytes Anti-Malware PRO [24-hours]

Description from developers page:

Malwarebytes technology takes the next step in the fight against malware. Malwarebytes Anti-Malware PRO detects and removes malware where even the best known anti-virus and anti-malware applications fail. Malwarebytes Anti-Malware PRO monitors every process and stops malicious processes before they even start. The Proactive Protection Module keeps your system safe and secure with advanced heuristic scanning technology.