Purpose: the purpose of this guide is to set up a "sandboxed" environment on a system that already has a9lh installed. What I mean by sandboxed, is basically an environment where it's difficult (or even impossible) to access a CIA installer. For most people this probably isn't ideal, as it obviously makes things a little more difficult to work with when you DO actually want to install something, however this is a good idea if the system you are working with belongs to a child or a non-technichal person, as it can prevent mishaps such as accidental uninstallation of games ( or far more dangerously, system files) or if you have a heavy preference for a stock looking system, and don't mind the extra steps that it takes to set up. This might also be helpful to those intending on borrowing their system to someone else as well... This is NOT meant as a replacement for a guide of setting up a9lh, but rather is an optional addition to it. Prerequisite: A system that you'd like to be locked down, after setting up a9lh. Information for setting up a9lh can be found here: http://gbatemp.net/threads/full-sto...u-need-to-know-includes-otphelper-now.417606/ Some of these might also be able to be applied to Menuhax setups, however some may require additional tweaking to make it cooperate with the auto-booting of a cfw. I've set up a handful of systems for others, but there's always been a bit of a looming shadow overhead, as the guides out there for setting up a9lh always leave FBI installed on the system. This certainly isn't ideal if the system is to be used by people that aren't particularly knowledgeable as to how the 3ds is actually set up (i.e. children, family members/friends that don't really grasp how the exploits work, etc.). I've come up with a couple of ways to help mitigate this issue, or even completely resolve it, these are as follows: 1. Probably the best way to do this requires an exploitable game, and (if not Cubic Ninja) a way to update the exploit exploit to work with whatever system version is needed (i.e. powersaves or another exploited console). You can simply reinject the original Health & Safety app over the one that's used for the process of setting up the system, using decrypt9. Keep a copy of Homebrew Launcher installed on the SD card, as well as a copy of FBI in the 3ds folder. Utilize your secondary exploit as required to do any further installing of CIA's going forward. Also, if you haven't yet done so, remove all files from the payload folder in the cfw, so they aren't accidentally triggered at boot time. Taking these steps will effectively sandbox the system, and make it effectively impossible to screw anything up on it. 2. This is similar to above, but a little bit more obnoxious to set up. Upon each time you're done using the system (uninstalling/installing whatever needs to be), inject the original H+S app over the existing FBI one with decrypt9. This doesn't require a secondary entry point (as the payload can be simply loaded via the a9lh payload folder), but is kind of a maintenance headache. Also upon each change, you should delete the payload for decrypt9 (as well as any other payloads that are sitting in the folder). 3. This isn't quite as foolproof as the above idea, but still isn't a bad idea if you don't have a cartridge to gain access to the system, and aren't too fond of the idea of wiping out/reinstalling FBI each time. Simply create a folder, and move FBI into the folder, then move the folder ALL THE WAY to the far right in the menu. This will keep it "out of sight, out of mind", as long as the menu isn't set up as a grid layout. Once again, as per the above method, also removing the files from the payload folder is ideal for this. 4. Install an FBI cia after being completely set up. Inject back the original H+S app. Remove the SD card, and rename the folder that FBI is installed to, to another name, for example: 0f800100 folder to 0f800100 (FBI) within SD:/Nintendo 3DS/bla/bla/titles/00040000 folder. Note: This breaks the link of FBI to the SD card, so it DOES effectively sandbox the system, however the system will throw an error about SD card being removed, and may have some side effects in the data management. This is also not a very well tested method, so if people could test this more and give any additional suggestions for improvement, it would be much appreciated. Credit to CheatFreak on IRC for this idea. 5. Install hbl cia (if it's not already there), and restore H+S back to stock. Access FBI via hbl only, and wipe out FBI from the 3ds folder (as well as anything else that might have system access) whenever not needed. 6. If the system in question has parental controls enabled, a modified copy of FBI intentionally locked down with parental controls can also work, a modified copy can be found here: http://www94.zippyshare.com/v/AZSVGbUv/file.html (Credit to LiquidFenrir) note this method can be set up as long as you have a pin for parental controls, even if you don't have any restrictions set for game ratings, but may conflict with out of region cias, causing the password prompt upon each launch. I'll be adding more methods/expanding upon the current ones as time goes on, so we can eventually have a comprehensive guide on this.