Freeware Utilities

Anti-Spyware, Anti-Virus, Anti-Rootkit Freeware Utilities

Check if there is a rootkit installed on my computer

RootkitRevealer is an advanced rootkit detection utility. It runs on Windows NT 4 and higher and its output lists Registry and file system API discrepancies that may indicate the presence of a user-mode or kernel-mode rootkit. RootkitRevealer successfully detects all persistent rootkits published at, including AFX, Vanquish and HackerDefender.
Check if there is a rootkit installed on my computer: RootkitRevealer by SysInternals

RootKit Hook Analyzer is a security tool which will check if there are any rootkits installed on your computer which hook the kernel system services. Kernel RootKit Hooks are installed modules which intercept the principal system services that all programs and the operating system rely on. If any of these system services are intercepted and modified it means that there is a possibility that the safety of your system is at risk and that spyware, viruses or malware are active.
The RootKit Hook Analyzer is for free and runs on Windows XP, 2000 and 2003 Server on both 32 and 64 bit editions.
Check if there is a rootkit installed on my computer: RootKit Hook Analyzer

Protect the computer against adware

Lavasoft makes it easy for you to protect your private information on your home computer, providing safety, security and peace of mind for you and your family.
Protect the computer against adware: Ad-Aware Personal
Protect the computer with a firewall: Lavasoft Personal Firewall

Protect the computer against spyware

Spybot - Search & Destroy detects and removes spyware, a relatively new kind of threat not yet covered by common anti-virus applications. Spyware silently tracks your surfing behaviour to create a marketing profile for you that is transmitted without your knowledge to the compilers and sold to advertising companies.
Protect the computer against spyware: Spybot - Search & Destroy

RunAlyzer is a brand-new autostart & configuration manager that allows you to view and edit all the spots where Windows looks for programs or services to start. It's a combination of a standard configuration manager and an advanced tool to locate and remove places where hijackers, spyware and other malware hide.

FileAlyzer is a tool to analyze files - the name itself was initially just a typo of FileAnalyzer, but after a few days I decided to keep it. FileAlyzer allows a basic analysis of files (showing file properties and file contents in hex dump form) and is able to interpret common file contents like resources structures (like text, graphics, HTML, media and PE).

RegAlyzer is a tool to browse and change the registry. I wrote it because of a few features I missed in the original regedit tool.

Windows Defender is a free program that helps you stay productive by protecting your computer against pop-ups, slow performance and security threats caused by spyware and other potentially unwanted software.
Protect the computer against spyware: Windows Defender

The efficient solution against the new generation of threats spreading over the internet. Secure your data and protect your privacy against sypware, adware, trojans, dialer, keylogger and worms. We offer you advanced scanning and detection methods and state-of-the-art technology behind an easy to use interface.
Protect the computer against spyware: AVG Anti-Spyware

Prevent the installation of spyware and other potentially unwanted software!
Spyware, adware, browser hijackers, and dialers are some of the fastest-growing threats on the Internet today. By simply browsing to a web page, you could find your computer to be the brand-new host of one of these unwanted fiends! The most important step you can take is to secure your system. And SpywareBlaster is the most powerful protection program available. Prevent the installation of ActiveX-based spyware, adware, browser hijackers, dialers, and other potentially unwanted software. Block spyware/tracking cookies in Internet Explorer and Mozilla/Firefox. Restrict the actions of potentially unwanted sites in Internet Explorer. SpywareBlaster can help keep your system spyware-free and secure, without interfering with the "good side" of the web. SpywareBlaster is freeware for personal and educational use.
Protect the computer against spyware: SpywareBlaster

A real-time protection solution against spyware!
SpywareGuard provides a real-time protection solution against spyware that is a great addition to SpywareBlaster's protection method. An anti-virus program scans files before you open them and prevents execution if a virus is detected - SpywareGuard does the same thing, but for spyware! And you can easily have an anti-virus program running alongside SpywareGuard. SpywareGuard now also features Download Protection and Browser Hijacking Protection! SpywareGuard is freeware.
Protect the computer against spyware: SpywareGuard

HijackThis: A general homepage hijackers detector and remover. Initially based on the article Hijacked!, but expanded with a lot of other checks against hijacker tricks. It is continually updated to detect and remove new hijacks. It does not target specific programs/URLs, just the methods used by hijackers to force you onto their sites. As a result, false positives are imminent, and unless you are sure what you're doing, you should always consult with knowledgable folks (e.g. the forums) before deleting anything.
Stop/cleanup homepage hijacking: HijackThis

Protect the computer against viruses

This tool checks your computer for infection by specific, prevalent malicious software (including Blaster, Sasser, and Mydoom) and helps to remove the infection if it is found. Microsoft will release an updated version of this tool on the second Tuesday of each month.
Protect the computer against viruses: Windows Malicious Software Removal Tool

AVG Anti-Virus Free Edition is a free anti-virus protection tool developed by GRISOFT for home use. We invite you to join the millions of satisfied customers worldwide who have downloaded the software and now enjoy the benefits of AVG Anti-Virus Free.
Protect the computer against viruses: AVG Anti-Virus Free Edition

Free virus protection for Windows 98/Me/NT/2000/XP and for Linux/FreeBSD/Solaris.
Avira AntiVir PersonalEdition Classic reliably protects your private computer against dangerous viruses, worms, Trojans and costly dialers. More than 15 million users worldwide trust in the reliable protection of Avira AntiVir. And this is no coincidence at all: Avira has gained several awards. The product combines first-class detection rates and ease of use with a top performance that protects your computer safely and hardly burdens older PCs.
Protect the computer against viruses: Avira AntiVirR PersonalEdition Classic

avast! 4 Home Edition is a full-featured antivirus package designed exclusively for home users and non-commercial use. Both of these conditions should be met! Our company offers the Home Edition free of charge, since, in our opinion, it is possible to avoid global virus spreading by efficient prevention; however, many users are not able to or do not want to pay for antivirus software. This page will show you the most important features of this program.
avast! Home/Professional now fully supports the 64-bit Windows platform.
Protect the computer against viruses: Free avast! 4 Home Edition

FREE Antivirus for All
BitDefender 8 Free Edition is your chance to use one of the world's most effective antivirus engines for free! BitDefender 8 uses the same ICSA Labs certified scanning engines found in other BitDefender products, allowing you to enjoy basic virus protection for no cost at all. BitDefender 8 Free Edition is an on-demand virus scanner, which is best used in a system recovery or forensics role.
Protect the computer against viruses: BitDefender 8 Free Edition

Virus Removal Tools. We provide you with a list of specialized utilities for virus removal. The utilities can be used to remove of some of the most common viruses. The list is updated on regular basis.
Protect the computer against viruses: Vcleaner

CWShredder finds and destroys traces of CoolWebSearch. CoolWebSearch is a name given to a wide range of different browser hijackers. Though the code is very different between variants, they are all used to redirect users to and other sites affiliated with its operators
Protect the computer against viruses: CWShredder

Protect the computer with a firewall

Safety.Net offers Internet security, content security and advanced Internet firewall protection for all your LAN computers, and trust controls to block unwanted or harmful applications from accessing the network. You can define granular user or computer specific access controls based on site, content, PICS ratings and time of day. You can monitor connection level network activity round-the-clock and view detailed reports to analyze traffic and usage patterns.
Deployment: Home User
Protect the computer with a firewall: Safety.Net

ZoneAlarm is free for individual and not-for-profit charitable entity use (excluding governmental entities and educational institutions).Easy-to-use firewall blocks hackers and other unknown threats. Systematically identifies hackers and blocks access attempts, automatically makes your computer invisible to anyone on the Internet.
Protect the computer with a firewall: ZoneAlarm