Topic: Wii Menu corrupted on my Wii U?

Anyway to fix it? I guess that's a perfect timing as the Wii Shop channel dies..

Do you have a message you get or screenshot?

I have what sounds like a similar problem.
When i try and switch from the Wii U menu screen to the Wii menu (by either putting a Wii disk in and selecting the game channel or going directly to the Wii channel) the system does it's normal reboot, the initial Wii screen is loaded but before i can press A the system switches itself off.
I have no problem playing it with Wii U games.
I don't know if a factory reset will resolve it, but i'd like another solution as i don't want to lose all my downloads.
Can anyone help?

I also get the corrupted message sometimes after the Health and Safety screen. So now what I do is keep pressed the + and - button on the Wii controller while the first screen is showing and press A. This I think enables Maintenance Mode but won't give access to SD card. Just enter and exit any game or application (like the Mii channel) and you'll have the SD card enabled again.

I got this one glitch that worked that I was on my Wii menu and I turned off my wii u console and the gamecube logo went on to my disc channel.