| John, all the advice above is good, but you're a bit misguided with your setup, unless you have Norton Corporate/Enterprise edition this cannot be pushed out to the other machines, it's a standalone version you have so you would need to install this on all machines and update on all machines. I would suggest using different AV's across the machines though to give a more blended approach if for example virus A comes along Norton might not detect it, whereas AVG would then virus B might get picked up by Norton but not AVG if you see what I'm getting at. | 
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