To me Norton is just doing it's job & blocking NetBus.
Run both of these to give your comp a good check over.
a-squared Free
http://www.emsisoft.com/en/software/free/
http://www.majorgeeks.com/download4281.html
a-squared (a-squared) is a complementary product to antivirus software and desktop firewalls on MS Windows computers. Antivirus software specializes in detecting classic viruses. Many available products have weaknesses in detecting other malicious software (Malware) like Trojans, Dialers, Worms and Spyware (Adware). a-squared fills the gap that malware writers exploit.
Update after installing.
ewido security suite free for Windows 2000/XP
http://www.ewido.net/en/features/
http://www.ewido.net/en/download/
Please use the online update after the installation. Only then can the recent signature database be transferred and installed.
A powerfull anti trojan suite.Anti-Virus programs offer insufficient protection against urgently growing threats like Trojans, Worms, Dialers, Hijackers, Spyware and Keyloggers.That's where the protection of the ewido security suite starts and supplements existing security applications to a complete security system, because only a complete security system works effective.
By combining the free AVG anti-virus scanner, the free version of Ewido anti-Trojan scanner and the free Microsoft Antispyware scanner, I managed to achieve a 95% detection rate against a
particularly nasty set of 104 assorted malware products that I had downloaded from P2P networks.
http://www.techsupportalert.com/issues/issue122.htm
http://www.techsupportalert.com/issues/issue123.htm
http://www.techsupportalert.com/best_46_free_utilities.htm
http://www.techsupportalert.com/issues/back_issues.htm
Trojan and Spyware Tool -- Ewido Security Suite
http://georgeh123.blogspot.com/2005/09/trojan-and-spyware-tool-ewido-security.html