Best Free Trojan Scanner and Remover

Emsisoft Anti-Malware (previously known as a-squared Free) is a good choice to scan and remove malware, especially trojans, from your PC. It removes reliably the trojans containing backdoors, keyloggers, diallers and other destructive pests which make it dangerous to surf the web.

Other than trojans, it also can be used to recognize and remove spyware, adware, tracking cookies, worms, viruses, and rootkits from your PC.

Designed for ease of use, this program combines Emsisoft Anti-Malware  and the Ikarus Anti-Virus engine in the latest version to cut down on unnecessary double detection routines for one and the same malware.

Any suspicious file/s can be uploaded to Emsisoft for analysis: www.emsisoft.com/en/support/submit/ and also, you may find their forums helpful: support.emsisoft.com/

Features such as quarantine, online updates and heuristic scan for unknown malware are included.

From the Emsisoft website, "When downloading, you'll get the full version including all protection features for 30+3 days for free. Afterwards the unpaid software switches to a limited freeware scanner mode that allows you to scan and clean your PC whenever you want, but does not include the protection features against new infections".

In other words, the free version does not provide other features such as file guard, behavior blocker and surf protection.

Malwarebytes' Anti-Malware is an on-demand scanner which can be used to find and remove trojans, along with other malware such as viruses, worms, rootkits, diallers and spyware.

While it will never win any prizes for its user interface, the program is intuitive and simple to use.

As there are daily updates, always ensure the software has been updated prior to scanning your PC. For those of a forgetful nature, you can set the program to warn about the database being outdated.

MalwareNET, which is an online database, revealed that nearly 20% of the total objects detected by MBAM were related to trojans.

Other features include: multiple-drive scanning;  quick scanning; ignore list; quarantine, to hold threats prior to deletion or restoration; along with various settings to enhance performance of the program. FileASSASSIN is also included to enable deletion of locked files.
 
Another plus point is MBAM rarely causes any conflicts with other anti-malware utilities. If you encounter problems that are not covered in the help section you can visit the Malwarebytes forum: forums.malwarebytes.org/

If you prefer an out-of-the-box solution with minimal user interaction, then  PC Tools ThreatFire is an excellent option. It offers proactive defense against both known and unknown (zero-day) threats from trojans, viruses, worms, spyware, rootkits and other malware.

ThreatFire provides real-time behavior-based malware protection. This is achieved by constantly running in the background and eliminates the need for on-demand scanning.

Nevertheless, PC tools have taken 'a belt and braces' approach with the added inclusion of a rootkit scanner.

Any malicious malware that is detected by this software is automatically quarantined to protect your computer. You can then upload the file for analysis to: www.threatexpert.com/filescan.aspx

Once you have ascertained that it is indeed malware (and not a false positive) you should permanently delete the threat from your system. The program interface shows you a world map, depicting the location of prevalent threats in the wild. However, of what use this is to anyone is beyond me!

Much more useful is ThreatExpert Reports, which gives detailed information on the latest 200 threats, with more than 30% of them related to trojans.

ThreatFire comes with a feature which allows you to help identify new threats and provide feedback to its Secure Community while you receive automatic updates from them. If you opt out of the Community, automatic updates will not be supported.

SUPERAntiSpyware is worth a try as well. In addition to its focus on detecting and removing spyware infections, this program deals with trojans and other types of threats such as diallers, keyloggers, worms, rootkits, etc.

It supports a quick scan, complete system scan or custom scan with trust items and exclude folders. The program also provides an option to check for latest definition updates before scanning to protect you from the newest threats. SAS also has a Trojan Threat List shown here. There are 100 examples of different dll and exe files, all of which should not be allowed to run on your PC. Clicking on any of the items in the list will give you a more detailed description of that particular threat.

Among other features, it includes Hi-Jack Protection which prevents other applications (excluding Task Manager) from terminating the program.

FAQs and help with false positives can be found over at: forums.superantispyware.com/

On the down side, the free version of this program does not support real-time blocking, scheduled scanning and some other features.