fritzbox 6490 fritz.os 7.20

[citarone]

hi I have the problem that the freetz firmware cannot be installed. get the message that it is not an original firmware. tried to downgrade got the same message what else can i try.

ps: am a noop please be as detailed as possible
pps: the fritzbox is an old one that otherwise no longer has any function

[fda77]

https://freetz-ng.github.io/ >> README

[pony1k]

there is a tool for that.
tools/push_firmware -h