This question already has an answer here: How do I get rid of malicious spyware, malware, viruses or rootkits from my PC? 15 answers How to remove trojan PB from windows 7 system? previously i had installed Norton 360 antivirus. the subscription was expired two months back. Recently i have purchased quick heal total security. while installing quick heal antivirus i get the message 'system infected by Trojan PB' Their is an option to remove Trojan PB by restarting computer. However the infection does not get removed. Please advice for removal of Trojan PB