Nikon Firmeware update

Get new firmeware files (1. firmware for body, 2. firmeware for lenses)

$ firefox https://downloadcenter.nikonimglib.com/de/products/25/D5300.html

download both

than start with firmeware update of body: called something like F-D5300-V103W.exe

$ unrar e F-D5300-V103W.exe

Extracts the file D5300_xxxx.bin Copy that one to the root fs of the sd card and perform firmeware upgrade via the cam. Now do the same for the lenses

$ unrar e F-DCDATA-2017W.exe

Extracts the file NKLDxxx.BIN Same steps as above