@Markmcquinn wrote:
Factory reset with the reset button does not work
That's a pity, but you'll have to explain in a bit more detail what you are doing and where things go wrong.
Can you access the browser graphical user interface (GUI)? If so, have you tried to use that to reset the device?
Visit the support pages:
Support | NETGEAR
Feed in your model number and check the documentation for your hardware.
Check the section in the manual Manage the Modem Router Configuration File
While many questions about routers are generic and could be answered anywhere, some things need specialist knowledge.
You might get more help, and find earlier questions and answers specific to your device, in the appropriate section for your hardware. That's probably here:
Cable Modems & Routers
