Moreover, if I try to extract the QSPI file “Jetson_Xavier_NX_QSPI_35.1.gz”, it seems to be not in a valid gzip format. I have downloaded the file on Windows/Ubuntu/Debian on 4 different machines with 2 different Internet connections. Everytime it is around 15MB in size but not in a gzip format (bad format). Please let me know how to get the jetson-xavier-nx-devkit.spi.img file which is needed to be flashed.
Yes. I followed the below procedure to reflash the board. There are some pre-req for the host machine which are not mentioned in the guide (qemu installation and libxml requirement), but overall this is the process which worked for me smoothly.
I don’t know where to download specific image files, but normally such a thing would be with the specific L4T release page: https://developer.nvidia.com/linux-tegra
So far as the file being invalid, under Linux, what do you see from: file Jetson_Xavier_NX_QSPI_35.1.gz