When attempting to start any game that is a 3ds game, Retroarch goes black for a second then it responds with “failed to to open libretro core.” However, I have reinstalled the citra core several times and made sure that is in fact in the right place. I have no idea what I am doing wrong. I can provide any screen shots if they will help.
What platform/OS? Can you get a log of you trying to load the core via ‘load core’ (i.e., without loading any games)?