I've been brought here by an acquantaince when I was asking about the problem that I'm facing as stated in the subject. I've recently bought a few GBA carts to play on my NDS while waiting out the recent drought of NDS games.
I have a few GBA carts but only 3 have this particular problem. Golden Sun, Metroid Fusion and Advance Wars 2 (pirated, so I will leave this out). I'm assuming that Golden Sun and Metroid Fusion are original products because I bought them in a reputable Hypermart. The problem Golden Sun has is that it will give me a "Save Fail" message whenever I try to save. I have tried that in all the 3 save slots and still the same thing, however, if I do it a few times, then it will show a save state but with the remark "Save File Corrupted". On the other hand, Metroid Fusion does not give me a "Save Fail" but rather it acts as though it is saved perfectly fine except that when I turn the NDS off or restart it, the save file isn't there.
The reason I posted this is because I want to at least understand why this is happening and how to prevent it from happening in the future when I'm purchasing my games and if possible rectify my situation.