I have installed Norton 2004 Personal Firewall on my laptop (note: firewall only not the full NAV). Now when avast! Pro starts I get an error message that says I am running Norton Antivirus and that some of the Avast services will not start, however this is incorrect as I am only running Norton Personal Firewall. What can I do?
You can try another firewall
I’ve paid for this one and it should work! Surely avast! should be smart enough to distinguish between NAV and the Personal Firewall?
Ooops! I’ve found the problem – the Sony recovery disc set had secretly installed NAV 2001 on the machine without notifying me. Now this has been removed all is OK again.
Surely 
Oh my god, Sony again, installing stuff you don’t know about ;D ;D
Good find, welcome to the forums.