Antispyware software should be used in conjunction with antivirus software and not as a replacement, antispyware and antivirus have different functions, antivirus software for example, does not warn you of tracking cookies, good antispyware software will not cause you any incompatibility when you run it alongside an antivirus the developers will have designed it with that in mind.
Free antimalware tools
SuperAntispyware: Light on system resources, it has been designed not to slow down your computer during spyware scanning, it works alongside anti-virus software without compatibility problems, a very thorough antispyware tool, scanning your files, computer memory and Registry, it’s custom scanning engine allows you to check external USB devices like thumbdrives for spyware and exclude folders you are known to be safe in order to speed up the antispyware scan.
MalwareBytes: Multilingual antispyware software that can detect spyware before installation and remove it if the computer has already been infected, the free basic version is very limited, it has no real time protection and no heuristics against zero day threats.
SpywareBlaster: It prevents installation of spyware, adaware and other malware designed to get into your system and invade your privacy. It doesn’t use any significant CPU or computer memory and will not slow down your computer while it protects your Internet browsing session, capable of running along other antivirus and firewall software.
Spybot Search&Destroy: This malware protection tool provides complete information on any spyware it finds, it works in the backgrouond protecting you against new threats not found by your antivirus software, in between others, it protects you against toolbars installing in your browser without your knowledge and homepage hijacking.
SpywareTerminator: Real time HIPS protection, after scanning your computer SpywareTerminator will show you a list with easy to understand information of all of the threats it has found, the entries are classified by risk level and the user can decide what has to be removed, integrated with ClamAV open source antivirus which is included with the antispyware software download.
Lavasoft Ad-Aware: The free version provides basic behaviour based heuristic technology able to detect zero day threats, rootkit removal, integrated with Windows Security Center, spyware scanning can be scheduled and customized pin-pointing Ad-Aware to single files or external hard drives, you can submit suspicious files to Lavasoft technicians for analysis with just a click.
Beware of fake antivirus and antispyware!
A well know multimillion scam is run by fake software pretending to be a legitimate spyware removal tool that is not able to detect anything and makes computer users believe that they have been infected by malware by showing them window replicating a computer scan with annoying popups and scary messages, in order to remove the non existent malware from the operating system the user must to buy an “upgraded” version of the software which then removes the fake malware warming message.
Stay out of brands you know nothing about, if you believe your system has been infected by spyware do as much research as possible on the Internet about the kind of malware you have, before upgrading to any paid for software whose brand you know little about inquire around first and most important of all, never install any pirated antivirus software in your system or buy it from dodgy sources, not only the updates for counterfeit antivirus will eventually stop working, but most times warez cracked antivirus software also comes embedded with a virus.