I purchased Norton Internet Security for Mac in Sept. 2010, and renewed the subscription in Sept. 2011. When I purchased the the software, I was able to install it on the four Mac laptops we own, but when I renewed the subscription, I had to pay for each installation on each of the laptops. I would've been better off purchasing the software at Best Buy again. Why doesn't Norton allow the subscription renewal installation on multiple computers, the way it does with the original software purchase? And if it does, can I get a refund?