I scanned with nod32 my computer 4 times.. and it found many viruses that i removed but.. it didnt delete a virus called WIN32/virut.nbk .. seems that this virus has infected all my programs.. (all .exe types ). it found more than 300 infections but only quarantined them . if i removed them it will mean to remove even system files.. so what should i do? the virus keeps restarting my computer.and I tried many antiviruses but only nod32 found that win32/virut.nbk but it doesnt clean it from files.. I have many important things in my computer so i cant format it..