How to guarantee that Adobe Acrobat Readerwill never auto update or updates through user action

Acrobat Reader auto-updates and there is no UI to turn it off. However, if you have a Reader Deployment License you can deploy it in the company and use the info in the Acrobat Enterprise Toolkit to set policies on updates and many other things, leaving deployment of updates in your hands. Enterprise Toolkit for Acrobat DC Products (adobe.com) Note that you will need a rapid response to available updates; they are often fixing critical security bugs and any company will want to install them as quickly as possible.