I bought the Norton 360 premiere 3 PC version about 13 to 15 months ago. As soon as I bought it, I installed it in one Notebook PC and my Desktop PC. I just bought a new Notebook PC and entered the product key as it should be valid for a 3rd PC. But it is not accepting it anymore. Does the one year validity run concurrently from the time the product is installed in the first PC? In that case, in fairness to consumers, the package or manual of the product must say so clearly somewhere. This is very disappointing!