In case with free trojan removers, the situation is changing all the time. About 3 years ago IT pros would name TDS-3 among best of breed programs created to remove trojan viruses. But the program ceased to exist, its support was discontinued. Other products appeared on the scene as promising trojan fighters, but their developers either lost enthusiasm or quit the programming, leaving the software 'half-cooked '.
So in brief, what was well-performing yesterday, might have been left in dust by new products. Some of the old players managed to keep up the pace, too. Therefore my short list of software effective in removing trojan viruses includes only programs that scored awards from trusted reviewers and security labs. I personally tested each program to ensure none of them contains serious bugs.
It is worth noting that popular antivirus software and Internet Security Suites from world-renowned manufacturers show relatively weak trojan virus detection capability. Even identified trojans happen to be too tough for an antivirus to erase them from the system. There are practically no exceptions to this sad fact; no matter what antivirus industry leaders promise to potential customers, their products perform as trojan cleaners with imperfect algorithms.
Spybot Search and Destroy: Perhaps the best free client software ever. Does not give active protection so you canstill get re-infected. Easy to use program and sure to hep out.
Malwarebytes free version: Our second choice for it being a free client. Good stuff. Does not give active protection so you canstill get re-infected
Smitfraudfix.exe: Free program that helps to remove Smitfraud and fake security clients. Very easy to use and does help with
A-Squared HiJackFree: is a detailed system analysis tool which helps advanced users to detect and remove all types of HiJackers, Spyware, Adware, Trojans and Worms. More specifically this works for zlob removal. =]