That happens when the OS can't be found. If it's already on the card try taking the flash card out and reseating it. Has your Edge card been crashing at all? Mine has and when it does it sometimes either corrupts the data on the card or wipes it completely so that could be why the error is...
My Edge card sometimes has problems when saving games (says saving and any music etc keeps playing but nothing else happens) and sometimes freezes when loading games. A couple of times now when resetting my NDS after a loading freeze the memory card has been wiped.
Is this more likely to be a...
I feel like school, back when I was actually in school, was more entertaining though, because of how much I get to interact with people, hang out with friends, and other stuff like that. All I get to talk to at work is my boring coworkers lol