There's a user on the official forum who only has the 2008 install CD so he can install it but he can't update it because ATX no longer has them posted on their website.
I don't mean you should download the latest update file, although if you install from CD and apply the update that will work. What I mean is to download the full installation file:
For 2016, go here: https://support.atxinc.com/download/taxprogram.aspx?taxyear=2016
When you're on the prior year downloads page (https://support.atxinc.com/download/prioryear.aspx), click on the links that say '20xx Tax Program' to find the install files.
And put a reminder on your calendar each fall to do this for the current year. The current year program is here:
https://support.atxinc.com/download/formdevelopmentstatus.aspx
and you click on the link that says 'ATX Tax Program'. Or you can edit the 2016 URL and change the 6 to a 7.
https://support.atxinc.com/download/taxprogram.aspx?taxyear=2017
You can see the version of the install file, after you've downloaded it, by viewing properties (right click on file, choose Properties) and going to the Details tab.
I actually download the latest full install file every time there's a program update, in case I ever need to reinstall it, to save having to run the updates.