: This is the most reliable official source for modern PCs. The version on GOG is pre-patched for better compatibility with newer Windows versions.
You're looking for information on downloading "IGI 2" for PC, specifically for Windows 8.1. Here's what I found: igi 2 download for pc windows 81 exclusive
: Offers the full version and a single-player demo if you want to test the game first. ZOOM Platform : This is the most reliable official source for modern PCs