The installer says "This version is too old" after downloading. Solution: ESET occasionally retires very old builds (over 6 months old). The latest/ folder always provides the current build, but if you saved the file months ago, re-download it from the official link.
ESET Smart Security Premium is a top-tier cybersecurity suite. Standard installations require a live internet connection to download setup files. An offline installer contains all necessary files in one package. This guide explains how to find, download, and use the ESET Smart Security Premium offline installer. Why Use an Offline Installer? eset smart security premium offline installer link