The process runs on my PC as described on the website. I am closing the browser when the installation process demands (firefox version 40, up to date) then installation makes further process . After some seconds a prompt tells me in German "Installation konnte nicht abgeschlossen werden , weil der Flashplayer läuft" - meaning "Installlation could not be finished properly as the Flash Player is already running. In fact the player does not run , I also deinstalled the old player and deactivated the add-on in firefox.
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