I got my WiiU last fall, and the first thing I did was transfer everything over from my Wii. But the Mii Maker has never worked. Every time I try to open it, the loading screen is up for a second or two before both the TV and gamepad screens turn grey and something starts making a buzzing sound (last time it was the console, but I think the gamepad has done it instead at least once). My personal Mii was able to transfer from the Wii safely, and I've been using it for all the games and software, but none of the other Miis that should have transferred from my Wii are coming up.
I already checked if the problem might be caused by overheating, but that's not it. Now I'm suspecting data corruption, but I don't want to mess with the saved Miis yet lest I lose the ones I had on the Wii - or worse, my personal Mii and all the game saves connected to it. Is there a way to somehow try and reinstall the Mii Maker software in case that's where the problem is?