Hi.
Please Update the system with latest Antivirus definition and do a full scan of the system and then run NPE tool on the system.
Please check the below article for best help.
http://www.symantec.com/security_response/writeup.jsp?docid=2013-080623-4310-99&tabid=3
https://www-secure.symantec.com/connect/forums/symantec-antivirus-detection-results-trojangen
http://www.symantec.com/security_response/writeup.jsp?docid=2011-082216-3542-99
http://www.symantec.com/security_response/detected_writeup.jsp?name=Trojan.Gen.2