I have a partition (FAT) for movies, and a WBFS partion for USB Loader. USB Loader will boot NSMB Wii just fine until I use Wii MC. Then it won't boot the game, but the program itself will load. It will not boot the game until I connect the external HDD back to my computer and eject the drives before reconnecting the HDD to the Wii.
Use one FAT32 partition for both your movies and games. Also, be sure your loader and cIOS are up to date.
SM 4.1 (v499) - BootMii/IOS v1.5 - HBC 1.1.2 - Priiloader 0.8b6 - d2x v9(r49) - WiiFlow 4.1.1
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Originally Posted by sven