3DS Save De/Encrypter is a Windows application for decrypting and encrypting 3DS save files. In addition this tool can also create a reset save file for restoring 1-save game carts back to factory defaults. Hardware such as the NDS Adaptor Plus with version 3.02 software is required to grab the save file from the 3DS game cart. For more information on this project and to get involved with the discussion, check the link below.
QUOTE(Change Log)
Decryption now places "FF" into decrypted file incase of CRC checksum miscalculations while attempting to calculate checksums. So now removed the need for backwards compatibility with 3DS SaveTool by crediar as it's no longer required.
Some people have said they needed a file to get the application running so added COMCTL32.OCX to archive for those people that need it.