How many times I have heard a client say, "I dunno how that happened, I had Norton". I do know that to many reading this I am singing to the choir but, just as point of interest... Today I worked on 2 computers for a client. Both had Norton; it was removed & MSE installed. Malwarebytes was, also, installed and run. In spite of the fact that the End User may think they are protected due to having Norton... Malwarebytes found 20 infections of worms, Trojans & such. To put it another way, one is NOT protected by virtue of an AV, alone. There must be malware protection, as well. And I will be so bold as to say, something better than Norton, too.