If you ever had programs unexpectedly installing on your system, popping up advertisements, saying voice advertisements or playing music, changing (hijacking) your home page (or start page), modifying your search results, displaying search results when you hit a 404 file not found page, dialing out, and so on, your system has probably been compromised by some spyware, adware, trojan, hijacker or dialer.
Loosely speaking, when this page refers to spyware, it means some program that has been installed on your system that reports something back to the software writer (or website that installed it) - whether it be websites you visit or your activities on the computer or the like. Adware means a program that displays advertisements on your computer; and I don't mean the usual advertisements you see on web pages that you visit: adware pop-up advertising windows (or in some cases, say some voice message) on your system are not generated by the websites you happen to visit. Dialers are programs that get installed on your system and try to dial up to some telephone line somewhere, sometimes incurring you expensive phone bills. Keyloggers record the keystrokes you type on your computer (some are more sophisticated in capturing screen shots, etc), and either log them or report them to the person who installed them.
This page lists some sites and software that you can use to detect such spyware, adware, trojans, hijackers, dialers, keyloggers and what-have-you on your computer. Some of them will also remove them, and others when installed and run will prevent some of these nasties from being installed in the first place.
Note that this page does not list commercial anti-malware software like Norton Internet Security 2009 (which not only clean anti-malware like spyware, trojans and so on, but also protect you against viruses and include a firewall) or dedicated spyware/adware protection programs like Spyware Doctor (free trial available).
Free Spyware, Browser Hijacking (etc) Prevention, Detection and Removal
Ad-aware Free
Adaware detects and removes spyware, adware, trojans, hijackers, dialers, malware, keyloggers, rootkits, etc. They also have a more fully featured Plus edition with antivirus protection, etc. Note that the free version cannot be used in a commercial environment.
Microsoft Windows Defender
Microsoft Windows Defender for Windows XP and 2003 is currently available from Microsoft free of charge, subject to their verifying that your computer is running a legal version of XP. If you use 64 bit versions of Windows XP and 2003, get the 64 bit version instead.
Spybot Search and Destroy (Spybot S & D)
One of the best spyware detection and removal utilities is actually free. It can detect and remove spyware, adware, trojans, hijackers, dialers, malware, keyloggers and numerous other nuisances. It runs under Windows.
SUPERAntiSpyware -- AntiAdware, AntiSpyware, AntiMalware
This anti-spyware program scans your hard disks, removable drives, memory, and registry for adware, spyware, malware, trojans, dialers, worms, keyloggers, hijackers, etc. Besides being able to detect these threats, it is also able to remove them if they are found to have infected your system. You can also exclude certain files or folders from scanning if you wish.
a2 Free
a2 Free is an anti-trojan, anti-malware, anti-dialer and anti-worm scanning software. You use it to manually scan your system for malicious software like trojans, dialers, worms, backdoors, denial of service (DOS) tools, keyloggers, sniffers, and the like. It does a scan of processes in memory and the programs stored on your hard disk.
SpywareBlaster
This nifty program prevents spyware ActiveX controls from being installed on your computer by adjusting your system so that these malicious controls are prevented from being installed or run. For the technically inclined, it sets the "kill bit" for these controls, causing IE to refuse to run them. It also blocks cookies from certain websites or companies that are known to use these cookies to track a user's surfing habits.
SpywareGuard
SpywareGuard runs behind the scenes to block spyware from being downloaded or run on your computer. It also has the ability to prevent browser hijacking (whether it is your start page or your ability to search using a search engine or otherwise).
Sponsers
