Safely eject your SD card from your computer, insert it back into your 3DS, hold the required button combination (usually Start while powering on), and try launching the installer again. The application should now boot into the familiar SafeB9SInstaller screen seamlessly. To help narrow down the exact cause, please let me know:
Copy SafeB9SInstaller.bin (the extension might just show as a "BIN file"). failed to open safeb9sinstaller.bin
The 3DS cannot read the file because the SD card filesystem is corrupted or formatted incorrectly. Step-by-Step Solutions to Fix the Error Safely eject your SD card from your computer,
