Norton can't detect all viruses out there. If you want to be really certain it ain't a virus, then go to Norbie's site & follow his directions. He "is" an expert!!! Won't take too much time. NorbiesWorld (click on link)

Make sure your LW's settings are thus: Tools>Options>System Tray & make sure it's set to Shutdown immediately.

And don't download files smaller than 2,000 KB (2 MB)

If you don't wish to use LW then fine. Run away. That's what the spammers of viruses want you to do. These are such groups who are sponsored to spam the network: (a) Overpeers, (b) MediaSentry, (c) Mediadefender