If you own a Nintendo 3DS or 2DS console, you are probably aware of CFW. Custom firmware is very useful for a lot of reasons.
Installing a CFW can be a bit tricky. One obstacle which I personally encountered during a CFW install, was the infamous ARM 11 error.
I was curious to see what the newly released Luma3DS 10.0 CFW had to offer, and was trying to get the homebrew launcher running via the Rosalina menu. Once I exited the Download Play app, and re-opened it to open the homebrew launcher, I got the screen that you see above. This step which is a usual part of the install, should have worked, but it didn’t.
This tutorial assumes that you are familiar with the popular and well-written guide on 3DS Hacks.
What didn’t work for me
Let me save you some time and tell you what not to do. Naturally when I thought the app wasn’t working, and tried a different one. A commonly recommended fix, is to use the Health and Information app, which is pre-loaded on the Nintendo 3DS. But when I tried it, the console threw the same error.
I also tried the Luma configuration menu’s options, which includes the Game patching, and disable ARM 11 errors, to no avail.
How to fix an exception occurred error on Nintendo 3DS
- Begin by powering off the console.
- Connect the SD card to your computer, and go through the following folders:
- 3DS folder – This should contain the ctr-no-timeoffset.3dsx and FBI.3dsx. Do NOT place your boot.3dsx file here.
- The root folder of the SD card – It should have the boot.3dsx file.
- If any of those are missing, download and copy them to their corresponding folders.
- Open the Download Play app. Once it displays the 2 options, try launching the Rosalina Menu using the key combo: Left shoulder + Down + Select. Set the Switch the hb. title to the current app”, and then press B twice to exit the menu.
- Close the Download Play app, and re-open it. The homebrew launcher with the CTR and FBI options should now be displayed on the screen.
In my case, I had to re-download the boot.3dsx file and put it in the root of the SD card. I also managed to confirm this was the fix, by deleting the boot.3dsx file and was able to produce the error screen successfully. The only other files involved during the process are the CTR and FBI. So, you may want to try replacing those too, in case the fix didn’t work for you.