I'm afraid I have exactly the same problem, and that Joanne has rather missed the point in her reply. Yes, my (current, regularly-updated) Norton Anti-Virus is very good at spotting Trojans, and normally manages to quarantine them as stated. But when I attempt to delete them altogether, NAV almost always fails to do so, "Cannot Delete" being the usual informative message. I've often wondered about this, and have been very unsuccessful in getting any further answers or assistance even from Norton in the past. As far as I know, all of my previously-found Trojans are still sitting happily on my hard-drive (although in "quarantine" and therefore, I understand, functionally inactive) but I don't know of any successful way to get rid of them altogether. I'll now have a good look at the site that PaulB has pointed us to...!!