Systems that also infested but where anti-virus programs from other companies were in use could not be moved to the proper running. Only after Norton was used, the computers running again and the years.
Particular praise is still the free Norton Power Eraser tool. This could even be saved calculator that made no sound of sheer viruses more.
Acclaimed programs such as Panda, Avira, etc ... brought more problems than I would have been so fun. At Panda, it was so, that after installing the machine was no longer working and I had to perform a data recovery software and it was at that time even winner.
With Norton's never happened to me something. Therefore deserved 5 stars.