NxNandManager: reading and rewriting a Switch NAND image

The project is unmaintained, and the README says where to go instead

NxNandManager is a Nintendo Switch NAND management tool, and the first thing in the README is a status notice rather than a description. The project is no longer maintained by its original author, and you can find contributor builds on the repository's own actions page or download an updated version from two trusted forks, THZoria/NxNandManager and sthetix/NxNandManager.

That notice is the most important fact about the project and it shapes everything else. The badges still say latest stable release 5.1, and the release history confirms the shape of the timeline: v5.2 on 2022-04-20, v5.1 on 2022-02-01 and v5.0 on 2021-05-17. The last push to the master branch was on 2026-10-01, so the repository is not frozen, but the published versions stopped in 2022 and the maintenance burden has moved to forks.

The licence is GPL-2.0, the primary language is C++, and the topics are emunand, nintendo-switch and switch-nand. The repository layout is small, with a NxNandManager/ directory holding the application, a doc/ directory, and the README itself.

So the honest way to evaluate this tool is as a well documented piece of homebrew infrastructure with a maintenance gap, where the choice of build is the decision you actually make.

What the program does, in the order the README lists it

The capability list is long and specific, and reading it tells you what the tool treats as first class.

Backup or restore any Switch NAND, as a file or a drive: full sysNAND, full emuNAND, boot partitions or user partitions. Encrypt or decrypt native encrypted partitions, and the list names them, PRODINFO, PRODINFOF, SAFE, SYSTEM and USER, using BIS keys. Resize your NAND, in the USER partition only. Retrieve and display information about a NAND file or drive, with the firmware version, device ID, exFAT driver and serial number, again using BIS keys.

Then the features that are more unusual. Splitted dumps are fully supported for backup and restore, though the program cannot split an existing dump nor split the output file in any case. There is an option to wipe console unique ids and certificates from PRODINFO, which the README calls Incognito. And you can enable or disable auto RCM on BOOT0.

Creating an emuNAND, file or partition based, from any NAND image, either RAWNAND or FULL NAND, is on the list too. The advanced copy feature handles passthrough zeroes, split output and zip output.

Mounting is what makes a backup usable. Any FAT partition, USER or SYSTEM, can be mounted as a virtual disk, and the README says to follow the steps to install Dokan's driver first. The Explorer is marked Beta and covers three things: the content of the USER and SYSTEM partitions, with the title name and id and the user name and id; listing, saving or extracting files from saveFS, the title saves under the /save folder; and listing, saving, decrypting or extracting content from NCAs, the installed titles, using hactoolnet.

How it identifies files, and why the filename matters

The supported file format section describes a decision that will trip you up if you do not know it, and it is worth reading twice.

The program does not check the file extension to detect if a file is supported or not. It looks for a specific signature inside the binary data, the magic number, when possible. If the file is fully encrypted, the program detects the type by inspecting the filename without extension and the file size.

So the extension is irrelevant and the magic number is what counts, except in the encrypted case, where the name and the size have to carry the information. The rule that follows is specific: a single partition file that is encrypted should be named after the partition name, so SAFE.bin, SAFE.enc or SAFE.whatever will work, while SAFE_01.bin will not.

That is a sharp edge. A file that looks right by name can be rejected, and the reason is that the tool uses the name to work out the partition type and the size to work out whether it is a split file. If you have renamed something during a copy or a download, that is where the restore will fail.

On the drive side, NxNandManager detects physical drives containing a valid NAND or partition, and the examples given are memloader drives, the tool for mounting a Switch NAND on a computer, and an SD card containing an emuNAND partition, either an SX OS hidden partition or an emuMMC partition.

So the detection strategy is consistent: content first, and the filename only as the fallback when the content is encrypted and therefore unreadable.

Mounting the NAND, and the three ways the hardware shows up

The mounting instructions cover three different setups, and which one applies to you depends on what your console has.

For sysNAND or emuNAND through Hekate, the steps are to launch Hekate or Nyx, version 5.2 or later, and go to Tools then USB Tools. You either select eMMC RAW GPP for sysNAND or emu RAW GPP for emuNAND, and you can mount BOOT0 and BOOT1 separately. Set Read-Only to OFF if you want to perform restore operations, which is a detail that matters: leave it on and the restore will fail, and the tool needs write access for that part.

Then you open NxNandManager, open a new drive with CTRL + D, and select the mounted drive, and backup and restore operations are available from there.

For an emuNAND on a partition, you mount the SD card containing the emuNAND on your computer, open a new drive with CTRL + D, and select the drive labelled FULL NAND.

For an emuNAND in files, you mount the SD card again, open a new file with CTRL + O, and open the first split file of your emuNAND. The README gives the two paths, sdmmc:\emuMMC\SD00\eMMC\00 for emuMMC and sdmmc:\sxos\emunand\full.00.bin for the SX OS emuNAND.

The pattern is that the tool can open a physical drive, a partition on a drive, or a set of split files, and it asks for the first split file in the last case because the rest follow by name.

The partition types and what each can be restored from

The NxStorage types table is the reference for the restore operations, and its third column is the part that carries the risk.

Every individual partition can be restored from itself, and from a FULL NAND with a partial restore, and every type except the two boot partitions can also be restored from a RAWNAND with a partial restore. The PRODINFO family and the BCPKG2 group, which covers the Normal, SafeMode and Repair main and sub partitions, carry the same options.

The two container types are where the difference is. RAWNAND contains the GPT partition table, PRODINFO, PRODINFOF, the BCPKG2 partitions, SAFE, SYSTEM, USER and a GPT backup. FULL NAND contains BOOT0, BOOT1, the same GPT partition table, the same partitions and the same GPT backup.

So the practical reading is that a partial restore from a container type is available for everything except the two boot partitions, and the boot partitions can only be restored from themselves or from FULL NAND. That is a real constraint when a console's BOOT0 is damaged, because RAWNAND will not supply it.

The full list of types is BOOT0, BOOT1, PRODINFO, PRODINFOF, BCPKG2-1-Normal-Main, BCPKG2-2-Normal-Sub, BCPKG2-3-SafeMode-Main, BCPKG2-4-SafeMode-Sub, BCPKG2-5-Repair-Main, BCPKG2-6-Repair-Sub, SAFE, SYSTEM, USER, RAWNAND and FULL NAND.

Editorial conclusion

Adopt NxNandManager if you want a readable, restorable copy of your own Switch NAND, because it handles the split dumps, the encrypted partitions and the virtual mounting that make a NAND image usable on a desktop. Do not adopt it as a maintained dependency, because the README states the project is no longer maintained by its original author and the last tagged release is 5.2 from 2022, so the maintained versions are the contributor builds and the two forks it points at. Before you run any restore, take a second backup, because the tool writes to the same storage it reads and the README is explicit that restoring a partial partition is a supported operation.

Frequently asked questions

Official sources

1. eliboa/NxNandManager on GitHub
2. Issues
3. License: GPL-2.0
4. README
5. Releases