Hi gbatemp.
I have just succeeded in installing CFW (Homebrew) on my 3DS by using my R4 SDHC Dual-Core RTS 2016 card.
I used the guide on 3ds.hacks.guide and after i was done with the guide i was proceeding to restore my flash cart, so i tried to insert R4iSDHC Dual-Core 20XX from the list to...