You should install Bootmii as boot 2 (Not as ios!!!) if you've an older Wii :P (To avoid most bricks with dop-mii) (Bootmii) Try to hold the reset button when your wii is booting. (Maybe Priiloader is installed) (Priiloader hacks can block wii updates...) (Priiloader) But why do you want to do that?by Naughx - FixMii
Sound like a banner brick... You could try to reinstall HBC with bootmini.elf (Load it from bootmii) ~Else ------ Create a fresh nand ------ 1. Backup your corrupted nand with Bootmii. 2. Create a new nand from your old nand with this program (Ohneschwanzenegger): (Read this page before using it!) 3. Install the system files with Ohneschwanzenegger by typing 4.3U, 4.3E, 4.3J or 4by Naughx - FixMii