ThreatFire AntiVirus is another free anti virus software package from PC Tools Company. It is available for you to download and use for free of charge. The program provides protection for your PC against attacks by detecting malicious behavior, such as capturing your keystrokes or stealing your data. The new edition of this popular free security program, adds an on demand signature based scanner, a mostly just for fun world map that shows detected threats, and a useful system activity monitor that provides a good deal of information on the programs and services running on your PC.

ThreatFire seeks out rootkits, heuristics based threats, viruses, worms, Trojans, spyware, adware, keyloggers, and buffer overflows. The software real time protection didn’t noticeably slow down our computer, and the customizable advanced settings were excellent. Users can pick and choose their preferred trusted processes and create rules for detection, such as scanning for SCR files created by an e mail client. You can also avail yourself of the scheduler, and create a system restore point before moving threats into quarantine. The IntelliScan took about 15 minutes on our machine, but it didn’t lock us into scanning mode. We were still able to check out other panes in the ThreatFire interface.

In independent tests conducted for PC World by AV Test.org, a German security program testing operation, ThreatFire’s performance was outstanding. It correctly identified 18 of 20 new, relatively unknown malware samples by looking purely at factors such as where the program came from, what changes it made to files or the system Registry, and whether the program attempted to send information to the Internet. It successfully blocked 17 of those 18 (one sample stopped ThreatFire before the block could occur), and it successfully cleaned 16 of those blocked (it left part of one infection behind).

The lightweight ThreatFire service and system tray process didn’t noticeably impact our test system while we surfed the Web and performed common tasks, and together they used less than 10MB of system memory. But security programs by nature have to reach far into your PC, and as a result they can often conflict with other software and cause trouble. In our tests on one heavily used PC with a wide range of installed programs and utilities, the computer locked up each time we attempted to run an on demand scan using ThreatFire’s signature scanner. You don’t need to run the signature scanner to get ThreatFire’s worthwhile behavioral protection, but such lockups are a good example of why you should be careful about installing too many security extras. ThreatFire’s thorough behavioral protection provides a worthwhile additional layer of security, particularly for shared or other at risk PCs. It’s all the more impressive for being free. As always, however, be careful about loading your computer down with security programs. ThreatFire is easy to use, instantly effective, and very light on system resources.