Hello everyone. First off, I used a 4GB SD Card on Wii U, which works perfectly fine, no problem. The 8GB SD Card I had in my 3DS works fine, no problems aswell. I decided to use the 8GB for Wii U, and the 4GB for 3DS, so I deleted some games to make space for the 4GB card and backed up the whole SD Card, so the Nintendo 3DS folder and the folders with the numbers. I formatted emuNAND to make an emuNAND partition on the 4GB SD Card and transferred the 8GB SD Card emuNAND to the 4GB SD Card. When I wanted to put the backup I made on the 4GB SD Card, I found out that I forgot to delete a game, so I went to the 3DS folder, and deldeted the biggest folder in the 3DS folder, and some folder with numbers. It appeared to be Smash 4 as the icon was still there, which I deleted from System Settings 3DS System Software. Like I said, the 3DS reads the SD Cards for a few minutes, so I could do that, so I didn't know there was a problem rightaway then. I started seeing the problem with the SD Card when my emuNAND was black screen after getting out of sleep mode. Sometimes even after a few seconds when I boot the 3DS again, I get a message 'Could not access the SD Card'. When I re-insert it, it reads again, but stops reading it after a few minutes again. What is the problem and why it behaves like that all of a sudden while the SD Card works on Wii U just fine? Summary: - Make 8GB SD Card backup. - Format 4GB SD Card emuNAND for use with the 3DS. - Transferred 8GB SD Card emuNAND to 4GB SD Card. - Upon trying to put the the backup I made onto the 4GB Card, finding out there was not enough space, deleted a title by going into the Nintendo 3DS folder\some numbers or something, appeared to be Smash 4. I did that on the PC btw. - Put the backup on the 4GB SD Card. - Deleted the Smash 4 icon off the Home Menu in 3DS Software. - Boot emuNAND, works fine. - Finding out that there's a problem. - Seeing the scary message: 'Could not access the SD Card.' - ??? What to do now?