Spybot Search and Destroy is another candidate that I have been using back in the days. I did find this article in regards to Spybot Search and Destroy 2.0 has bloatware issues With that said and to be fair, there are now new versions of Spybot such as Spybot 2 + AV (Home & Pro) and Spybot 2 Free but I have not used them, nor read any reviews as to how well they perform. Additionally, TeaTimer may conflict with other security tools which do a much better job of protecting your computer and in some cases it will even prevent disinfection of malware by those tools. If you don't have understanding how a particular security tool works, then you probably should not be using it. The user must have an understanding of the registry and how TeaTimer works in order to make informed decisions to allow or deny the detected changes. TeaTimer monitors changes to certain critical keys in Windows registry but does not indicate if the change is normal or a modification made by a malware infection.

Most people don't understand how to use Spybot's TeaTimer and that feature can cause more problems than it's worth. See here - (scroll down and read under Freeware Antispyware Products). FYI: is no longer recommending Spybot S&D (or Ad-Aware) due to poor testing results.

Spybot search and destroy free 1.