The encryption key is kept only on paper. Get an SD card ready for restoring the encryption key.

  1. Prepare an SD card that has been initialized in FAT16 format.
  2. Using a PC, create a folder in the SD card and name it "restore_key".
  3. Create a folder in the “restore_key” folder and name it the same as the machine’s serial number, “xxxxxxxxxxx” (11 digits).

  4. Create a text file called "key_xxxxxxxxxxx.txt" and write the encryption key.

    Write this string at the head of the file.

    Use all lower-case letters.

    Do not use quotation marks, line break, or blank spaces.

  5. Save the text file in the "xxxxxxxxxxx“ folder created in Step 3.

    /restore_key/xxxxxxxxxxx/key_xxxxxxxxxxx.txt

  6. Turn the power switch ON.

  7. Check that a message “SD card for restoration is required. Please call service” is displayed on the LCD.

  8. Turn the power switch OFF.

  9. Insert the SD card that contains the encryption key into the machine's rear SD card slot.

  10. Turn the power switch ON.

    The machine will automatically restore the encryption key to the controller board.

  11. After “Restoration complete. Turn the power switch off, then on.” is displayed, then turn the power switch OFF.

  12. Remove the SD card.

  13. Turn the power switch ON.