The whole system is a bait and switch.

The problem was that the chrome default was set to never connect to the internet.
This was the installation default and not mentioned in the help screen

Once I got this running I found that adding the one year registration to the cart ended up with an empty cart.

If i added the 2 year discount price item to the cart I got a server error.
This left me with the choice of purchasing at full price.

I was sufficiently annoyed to go and purchase AVG