Good Free Windows Security Tools

Here's a list of free Windows security-related programs I've tried and which seem useful:

Free Anti-Virus

• AVG Free Anti-Virus
  
• Note: Perform a Custom install and don't install the annoying LinkScanner
  
• Not currently recommended
  
• PC Tools AntiVirus Free Edition
• Working fine on my Mom's Vista Laptop but ran into 100% cpu problem on friend's PC.
  
• Comodo Antivirus
• It was a nice light-weight anti-virus program, but I don't like that it now includes a firewall.
  
  

Free Spyware Search and Removal:

• Spybot - Search and Destroy
  
• Trend Micro HijackThis
  
• Note: you can analyze the HijackThis log file with these sites:
• http://www.hijackthis.de
  
• HijackThis Log Analyzer Beta 2
  
• Malwarebytes' Anti-Malware
• SUPERAntiSpyware Free Edition
• Not currently recommended:
• Ad-Aware: I haven't tried it recently and there seem to be lots of complaints about it.
  
  

Free Spyware Protection Programs:

• SpywareBlaster: Light on system resources since doesn't need to be actively running.
  

Process Identification

• Process Explorer