If you’ve just downloaded a repack of USB Loader GX (perhaps from a pre-configured pack like “ModMii,” “WiiFlow Repack,” or a pre-made SD card image), you’ve likely been greeted by a frustrating white wall of text. At the very bottom, the fatal line appears: "Switching to channel list mode" You click "OK," and instead of seeing your beautiful library of backup games, you get... nothing. The dreaded Wii system menu.
This error is the single most common roadblock for Wii homebrew users. When you’re using a repack (a pre-configured set of files created by someone else), the problem is usually not your hardware, but a between the repack’s settings and your specific USB drive setup. wii usb loader gx usb device not initialized repack
The Ultimate Troubleshooting Guide