Guys Good News, i install today Rasbian OS Jessie for my Raspberry pi 3 model B and what happends hoooola nothing. haha No Error nothing fail. MagicMirror install all without a Error, OS Stretch sucks for the MagicMirro so Guys never Use that. Use OS Jessie for The MagicMirror. PEACE!! It works now YUHUUUUU. Thank you all for helping me :D now i build the Frame and install a few Modules. Thank YOU ALL!!