im gonna try to explain you
1- make a backup of your "a lot of numbers and letters emunand folder" on your pc then delete it from your sd card
2- boot the emunand with rxtools and it will create data then turn off your 3ds
3- copy and paste the NEW "alotof numbers and letters emunand folder"...
u just have to delete the folder linked to your emunand that was created in 3ds folder of your sd card then but u are going to lose all the games you had installed from cias this is de easy way .. then if you dont want to lose info try to do this
1) In our SD card, inside the "Nintendo 3DS "...