Achoshare: List of Free Computer Security System

The products are almost exclusively free with some exceptions: products where there is no free alternative, good products that offer a lifelong license, and exceptional products.

Please inform me for dead/false links, and give suggestions for new applications with the form located at the end of this list. I react to every correction and suggestion, although I may not answer all of them explicitely. This list is updated approximately twice a week, if needed. So, if your suggestion does not appear to the list immediately, it does not mean it has been omitted.

Realtime protection

Anti-virus:

Avast!

Microsoft Security Essentials
Avira AntiVir
Panda cloudantivirus
AVG Anti-Virus
Fprot (with Returnil)
Ad-Aware
Spyware Doctor with antivirus
PC Tools Free AV
Preventon
Rising
Zillya
Nano
Kingsoft
Clam Sentinel

Anti-malware (Can be run alongside with an AV):
Prevx
Immunet
Clam Antivirus
Rising PC doctor
Hazard Shield
Windows Defender

Security suite (anti-virus, anti-malware and firewall):
Comodo
Forticlient

AV/AM trials:
Emsisoft (works as scanner after trial period)
Kaspersky
Avira
Nod32

Portable antivirus/antimalware (can be run with UBCD4Win)

DrWeb cureit

Emsisoft Emergency USB Stick files Superantispyware
VIPRE Rescue
AVZ AVZ database
Norman malware cleaner
Trendmicro Sysclean
ClamWin portable

Anti-rootkit

Gmer
Kernel Detective
RootRepeal
SpyDllRemover
XueTr
VBA anti-rootkit
Sophos
Sanity check
Gmer: mbr-rootkit
Gmer: catchme (user-mode)
Rootkitty (boot cd)

Online-scanners

File scanning with several scanners:

Virustotal (Uploader)

Novirusthanks (Uploader)

Scanning of several zipped files:

Online-scanners:

Firewalls

Limited versions of commercial firewalls:
Outpost
Online Armor
Zonealarm

free Firewalls:
Comodo
PCTools
Sunbelt
Privatefirewall
Jetico
Iolo
Sotfperfect
Sygate
Webroot
NetVeda Safety.Net
Ashampoo
Filseclab
R

Simple firewall:
Ghostwall

Windows firewall:
XP firewall guide
Configuring XP firewall
Vista firewall guide
Vista firewall control
Windows 7 firewall control
Sphinx
Diagnose and fix Windows Firewall service problems

Gateways:
Endian
Untangle Smoothwall

Replacement for router firmware:
Tomato
DD-WRT

HIPS

Behaviour blocker:
ThreatFire

Classical strong HIPS:
Malware Defender
Comodo defence+
Spyware Terminator
Real time defender
System Safety Monitor

Classical lightweight HIPS:
Winpatrol
System shields
Arovax Shield (XP,V)

Startup monitoring:
Startup monitor

Registry protection:
MJ Registry Watcher

Anti-executable:
Process Guard (XP)
Trust-no-exe
Winsonar

Drive firewall:
DriveSentry
SensiveGuard
CoreForce
PE Guard $

File/Folder Monitoring Software:
Tiny Watcher
SilentNight Inspector
FileChecker
FileMap by BB
Osiris
TheFolderSpy

Anti Dialer:
A-Squared Anti Dialer
Dialer shield

System hardening-HIPS

System & Program Files Protection:
System Protect

Prevent other users deleting files/folders:
Prevent

MBR protection:
MBRguard

Memory firewall:
Comodo memory firewall

Address space randomization:
WehnTrust

Prevention of drive-by-downloads:
Blade

Prevention of exploits in media files:
Quttera

USB-firewall:
No Autorun
USB protect
Net Studio USB FireWall
Ninja Pendisk!
Autorun Eater
MxOne
USB WriteProtector
USB Drive Antivirus

USB protection (other):
USBDummyProtect

Shutdown prevention:
Shutdownguard

Anti-keylogger

SpyShelter
Quaresso
CoDefender
Snoopfree
DataGuard AntiKeylogger
KL-detector
PSMA

Sandboxing-virtualization