Unable to mount CTRNAND or load the CTRNAND FIRM

[anameunknowni]

I tried to update an old 3ds xl from 11.4 to 11.7, but this error message showed up after all the files downloaded:

An error has occurred:
Unable to mount CTRNAND or load the CTRNAND FIRM.
Please use and external one.
Press any button to shutdown.

[profi200]

The NATIVE_FIRM is not installed correctly. There is probably more messed up. You need to do a CTRTransfer: https://3ds.hacks.guide/ctrtransfer