So, I bought a 128GB Sandisk Micro SD from best buy for my New 3DS. A legit one. I formatted the SD card to be NTFS (because I misread some directions), put it in my New 3DS and saw that it worked. All the games worked just fine with no problems other than slightly longer load times. However, I had used my old laptop with a built in SD port to format it, and because it was Vista I only got about 21.3GB out of it. So I found a SD USB Flash drive, put it on my window’s 7, and format it again to FAT32 and also got all 128GB (which is really about 119GB). So when I tried to put my save files back onto that SD card via the USB device for whatever reason I keep getting this error: “Cannot read from the source file or disk”

I get this error no matter which OS I use (Vista, 7, or Mac), and I have done this so much that it has actually corrupted two micro SD cards. I am currently on my 3rd one. I formatted it to FAT32, but went back to 21.3GB via the built in SD port on my laptop. It is transferring now, VERY slowly (about .4GB in the past hour and a half out of 17.8GB), but it appears to be working. I also followed this method precisely (after my little NTFS mess up).

So has anyone else had this issue with a 128GB SD card? Are my save files just corrupt? Or am I missing something here? I am starting to think maybe the USB SD Flash drive was wonky. Because using the built in USB slot seems to be working, but I can’t utilize all the memory on that OS.