This tools is designed to help you find latest available software or map update for your Audi MMI system.
All you need is to find out your current MMI software version, usually you can find it in Red Engineering Menu, more about how to find that, you can find on this manual (click)
In above photo we have highlighted MMI 3G Plus software version. You need to rewrite whole that version for EXAMPLE: HN+_EU_AU3G_K0942_3
do not use space instead of underscore_.