I have decided to look into this error since no one seems to get around it. Modding the Wii U doesnt cause this error just so you know. I purchased a wii u and after hours of research & process elimination... I have traced this problem back to the "Wii to Wii U transferring feature." if the wii console in question has been softmodded it doesnt matter what the source of the wii u state is...modded or not. Do not use this feature on modded consoles. It will cause a permanent update error block.