Attempting to decode error C82044B4, I get that the FS driver is complaining about a file "already existing", which hardly makes sense given the circumstances...
I would say, make a nand backup (like you always should before trial and error problem solving), then rename 0:/Nintendo 3DS/ and delete the random-named folder inside 1:/data/ - this would be somewhat equivalent to the factory reset you want to try (except by not generating a new SD key, but we're renaming the Nintendo 3DS folder to compensate)
The special factory version of 11.4, in fact, not the publicly downloadable one