"Exception 0400" via LetterBomb

My Wii's CD drive is broken, so I thought I'd install HomeBrew. Only possible way is LetterBomb, so I got the installer (from the red wire thing with the MAC address) and put it on the SD card. Into the Wii it goes and I get a message (but dated yesterday for some reason). Click that "and BOOM" as the instructions say, but then almost immediately after I get a core dump or something with "EXCEPTION 0400" in the middle of it.

Google found nothing for this string, so here I am.

It's a 4.3U system menu and a couple years old. After I click on the letter bomb some stuff scrolls by and then it just freezes here until I power off.

The boot.elf file on your SD card is corrupt.

The boot.elf(.dol) file is broken.Re-download the Letterbomb.zip