According to Microsoft, 50% of all windows based problems are caused by trojans, viruses and spyware. http://www.spywarelive.com has relevant software on combating spyware and its sources.
Proactive anti-malware program to clean and protect your PC from all internet threats: ransomware, viruses, spyware, Trojans, bots, adware and worms. Uses 4 layers of protection: Surf Protection, File Guard, Behavior Blocker and Anti-Ransomware.