COMODO Firewall Pro 5.1

Comodo Firewall Pro introduces the next evolution in computer security: Default Deny Protection (DDP™).

What is DDP? Most security programs maintain a list of known malware, and use that list to decide which applications and files shouldn't access a PC.

The problem here is obvious. What if the list of malware is missing some entries, or isn't up to date? DDP fixes this problem to ensure complete security. The firewall references a list of over two million known PC-friendly applications. If a file that is not on this safe-list knocks on your PC's door, the Firewall immediately alerts you to the possibility of attacking malware.

All this occurs before the malware infects your computer. It's prevention-based security, the only way to keep PCs totally safe.