|'using nod32 free trial anti virus'|
if you didn't purchase that I would suggest uninstalling it; also if you had McAfee or Norton installed, I would suggest that you go their websites and use those uninstallers. Just add/remove will NOT remove all the registry entries so no other AV will work properly.
Then I woud suggest installing avast free and then getting it to do a bootscan on reboot and moving all it finds to the chest.
That will probably clear up your problem for you.
You can also uninstall trojan remover and hitman pro if they are coming up clean.
Some HELP in posting on Computing.net plus free progs and instructions Cheers