and if is networked with other computers disconnect it from them.

I goggled " free Trojan cleaner"
here is the results
http://www.google.com/search?hl=en&q...=Google+Search

I like to get downloads from CNET download.com

here's a listing of the cnet editors top free removers -
http://www.download.com/sort/3150-80...&fileSize=&qt=

if you can scan it with those and get it removed
then get a registry cleaner - like ccleaner to clean out any remaining traces of it.
then after it's cleaned do a back up of your important files
and install the threatfire program to assist the nortons AV.

Is your Nortons only AV? does it cover spyware,etc too?

Now I always use an internet suite product - covers Anti Virus, AntiSpy, wifi, email, IM even parental controls & ID protection if you want it.
I bought a year of Zone Alarm for 3 computers - only 49.95 I believe.

I use the threatfire along with it too.

Zone alarm info & comparison- {most of these products & the main brands have a free trail of 30days or so to see how you like it or not.}

http://www.zonealarm.com/store/conte...try=US&lang=en