[EDIT] Hijackthis log has been updated. Ok,I've done everything as suggested in https://www.techspot.com/vb/topic58138.html including the removal tools that I first thought were bad. I believe I've removed a whole load of virii/torjans etc. Ive tried to reinstall NAV but just before it completes it stops, removes everything and says the installation was interupted. Could this be another virus?