Spybot Search & Destroy
One of my favorite computer security tools is Spybot Search & Destroy. As its name suggests, Spybot S & D searches your computer to detect spyware and malware, as well as proactively immunizes your system from spyware and malware attacks.
Spyware often infects computers when users open suspicious attachments or click links received in emails or on spyware inhabited websites.
Spyware can hide itself deep in the Windows registry, and can be very difficult to detect. Spyware "spies" on computer activity, such as what websites users visit and how often users visit them, often transmitting captured information to third-parties. Some spyware use what is called a "keystroke logger" to record the keystrokes a user makes in order to capture user passwords, which can be pretty scary if you bank online or make online purchases where you enter credit card or financial information.
Spyware can also use available memory or bandwidth without your knowledge, effectively making your computer a "zombie", and when used in concert with thousands of other infected computers, is part of a "DDoS"(Distributed Denial of Service) attack on web servers or large servers in a malicious attempt to bring a website or server down.
Spybot Search & Destroy features the "Search & Destroy" Tool, which runs a "bot-check" that scans suspicious entries on the system. Suspicious entries are then displayed and the user is presented with the option to fix or ignore the suspicious entries. There may be times an entry doesn't need to be fixed. Many times anti-virus programs show up on security scanners, because of their close involvement with the registry.
Spybot S&D also offers an "immunization" tool that detects weak points in browsers installed on a computer and proactively provides protection from possible attacks.
There is also the Spybot S&D "tea timer", which keeps an eye on the registry and notifies users by a system tray balloon when any registry changes are made. Any registry changes brought to your attention when you have not installed or uninstalled a program can be spyware or malware activity.
Spybot S&D provides updates weekly, and you should check for updates and immunize your system at least that often.
You can download Spybot Search & Destroy at www.safer-networking.org.
However, no matter how many anti-virus or anti-malware programs you run, your best protection is your behavior online. Never click links or open attachments in emails or allow websites to install add-ons that you don't absolutely trust.
A good practice is to reformat your hard drive once per year, as this will clean any malware off your system as well as clean off accumulated junk in your registry that accumulates after installing and uninstalling programs, and will return your operating system to its "out of the box" condition.
Always back up important data before making major changes to your hard drive.