Never heard of it: Have you tried add/remove programs, ad-aware or other spyware ridding programs, what is the state of your anti-virus? Installed but not up-to-date would be my guess. Have you tried the old faithful msconfig.exe? Under what circumstances does the lop.com appear? Does your son realise how much I charge for fixing this type of problem?
I would reccommend getting a copy of Lavasoft ad-aware. Completely free and very easy to download and install. Should remove most spyware and associated componants.