Backstory (for those interested) I had just successfully got A9LH on my own N3DSXL, then my brother asked if I could do it to his. He has a o3DSXL, but looking at the 3ds.guide, the process was still the same. I got to the Decrypt9 step with no problems. At the part where I downgrade to 2.1.0, the "Auto CTRNAND Transfer" step (I'm not that dumb, I did the NAND backup), I got an error immediately after it checked the 2.1.0 file. I don't remember exactly what it said, but it was something along the line of file not found on SD. Unsure if it started writing to NAND or not, I returned to the Decrypt9 main menu, unmounted the SD, reinserted it, and tried again. No errors this time. I thought all was going well until I restarted the DS, and all I got was black screens and a blue light. I saw the warning about not having the SD card in while booting 2.1.0, but the SD card was actually plugged into my PC, getting ready for the A9LH install. If anyone has any clues as to what happened (what I did wrong), feel free to pitch suggestions. TLDR: Followed guide, something went sideways during 2.1.0 downgrade, have NAND backup, 3DS bricked. I am getting ready to hardmod my brother's bricked o3DSXL, but a little confused about flashing to it. I've seen plenty of tutorials on dumping the NAND, but very little on writing to it. I'm assuming it's straight forward, but it doesn't hurt to ask. Actual Question(s): Can I just write the 2.1.0 ctrtransfer.bin to the NAND and continue with the guide? Can I skip any steps and go straight to A9LH (doubt it, because of the OTP thing can only be taken pre 3.0)?